Persona 3 Portable is an excessively lazy port, done with little care or desire to create a better version of the original game. It all of it's gameplay changes are backported from P4, with little care to make them fit. The fact that knockdowns behave differently alone breaks most bosses, and while additions like skill cards and direct commands are welcome, they aren't enough to fix the game's fundamentally broken balance.
And that's just the pure gameplay, now it's already widely known that the visuals were not just downscaled, they were completely butchered. Get ready to NOT see any of the 3d scenes and animated environments and miss out on cool character details (did you know that Ken drinks out of a comicaly large mug?) and immersion, you are now a circle on a jpeg. And in the HD version, you are a circle on a terribly AI upscaled jpeg, with artefacts being so visible that you don't even have to look hard for them: most semi complicated world elements turn into a blurry mess. Not to mention the crunchiest audio possible. And the lack of anime cutscenes makes some of the best scenes in the game into an impossible to take seriously farce. Get ready to see the iconic awakening scene as an awkward 3D model clipping festival, with all of the suspence and excitement gone, as well as several other scenes misrepresented by horribly written flavor text. The fact that some people have the audacity to call that writing "VN style" is an insult to the concept of a visual novel.
The only "redeeming" part of this port is the female protagonist, who... Doesn't fit the game's themes and turns all the intentionally blue coloring into a disgustingly unfitting pink. Seriously, it's so bad that even the opening uses the color red for her. Enjoy reviving an important character (with NO gameplay benifit), ruining one of the best scenes in the game even further as well as dating an underage boy, since apparently that's what girls are into?... But hey, she is CUTE and has QUIRKY replies, so why should that matter, amirite sisters?
P3P is the sinlge worst way you can experience the game, and now it's also painfully obvious that its HD port is just Atlus double dipping to milk the maximum money out of the brand, with the actual proper remake coming later. But hey, look at other reviews! People love this. People are fine with this mess, and will gladly pay actual money for it. That's the fans which will eat up literally anyting named Persona, and will justify all the objectively terrible changes and plain laziness, because apparently self inserting as a cute girl makes it all worth it. With those people as their fanbase, I don't even blame Atlus for doing the minimal amout of effort when porting their classic games. And now people are already asking for a Persona 4 remake, because that's the game which definitlely needs it more than 1 or 2 apparently. Enjoy the world you created.

Despite what some people want you to believe, the story is not terrible. It is an OK addition to the main campaign, explaining what exactly happened in the ending, and what the real nature of Nyx was. Everyone was kept decently in character (some being better than others) with their development from the main story preserved.
The gameplay though is a giant 25 hour slog which forces the player to grind for almost every boss, with hardly any story present in between it. The game dumps you with story at the start and at the end, only showing you 5 minute cutscenes in between 2 hour grind sessions for the majority of the runtime. There's blatantly not enough story to justify the 25 hours.
Really, just watch the cutscenes on youtube and be done with it. I doubt you want an equivalent of 100 extra Tartarus floors on a higher difficulty after playing the main story.

This one is going to be complicated for me, but I'll try.
This game is often credited as "creating a genre" (which I'll address later) and being in general revolutionary. And after playing every previous game in the series (mainly in preperation for this one) I simply do not see that 10/10 perfect score.
Sure, it's a huge leap forward for the series: flawless animations, beautiful fully realized aesthetics and music, playtime of longer than 2 hours... But there's one issue here: Super Metroid came out 3 years earlier.
You see, there's a reason wht that game gets praised to bit: it reintrouces the rough formula from the first game, and pretty much perfects it. The game is long, but never fails to excite the player: even your average zoomie brain gets constant stimulation with new weapons, new movement tech, but counterbalances it with harder challenges which force you actually make use of those gadgets. The best part of it all, however, is the many uses the items have outside of opening color coded doors, as you generally get to use most of them anywhere: new beams hit harder, new movement items let you do more and move faster, new bombs can clear your screen etc. etc. and Samus at the start of the game is a completely different character from a demigod she eventually becomes at the end. And despite the long runtime, because of that, engagement never really drops, as new things get introduced at every turn, rewarding the player.
Now, here's SOTN whcih doesn't do that. Alucard, while a really cool character with a cool design, stays the fucking same throughout this long-ass dragged out adventure, and the only real movement upgrade he gets is a double jump. "B-but the bat and the wolf" -- nope, both are ass. The bat is a tool you get to fly places, but not a FUN form to interact it. Comparing with, say Space Jump from Metroid, which sometimes forces you to have proper timing, but most importnantly has no annoying animation to go though just to use, the bat form from SOTN is just a pain in the ass. AND you are forced to use it in the super secret "oh shit our game is too short let's pad out the runtime with more of the same but FLIPPED!!" segment just to navigate previously simple rooms. And the wolf? The form designed for speed? Yeah, this mutt can't jump. Should I even compare it to simply running as is to get speed in Metroid? And both forms get dropped when you get hurt too, because fuck fun I guess.
Due to the lack of real, tangible movement improvements, the game's exploration quickly becomes a chore. Underground caverns straight up have you travel to one side to unlock another boat spawn, to get to the other side to unlock water not hurting you. Both are useless outside of the caverns by the way, you just wasted your time as a part of the intended progression. And a lot of areas go like that: you MAY get a weapon/armor/item/familiar card, but most of the time you get a useless outside of a single room key item or some consumable. Oh yeah, consumables. This game has RPG elements, which means it must shower you in pointless junk you never use because that's what it means apparently...
The weapons you get are fun, but all essentially are used the same way. Some are slower, some are faster, some have special attributes, some have different hitboxes and all have different damage numbers. But they are always used the same way and hit in the same dirsction. For fucks's sake, none can be used vertically, they all work in the expected way. For the usual linear Castlevania game it would be fine, and even cool actually, but nah, we are wearing big boy shoes now, deal with that for 10+ hours. The rest of the "RPG" stuff in the game is just fluff, not really worth discussing. Items make number bigger, choose which number you want to get bigger now, not like it will change how your character plays. And using consumables has you scrolling trough menus to equip a shitstick which hits once for 30 damage and leaves you with an empty hand. Wow.
Now, why am I so angry at this game, which I didn't even really hate and in the end enjoyed it for what it was? Because I don't get it. Right under my review there are a dozen which call it a 10/10 "best in the series" masterpiece. I don't get what part of this game leaves them with such an impression. Is is this just the style alone? Am I just stupid? But oh wait, it created the word "Metroidvania", it makes this special? What even is this word?
Now, here's a spoiler, a redpill if you will: "metroidvania" is a meaningless buzzword created to classify other games with the names of the series it itself doesn't represent well: not all Metroid and Castlevania games are "metroidvania". And in fact, SOTN doesn't even exactly reinwent the formula, it attempts to replicate Metroid with it's own spin, which it does... Decently, actually. With how different the focus was, the game delivered well enough for the time, it successfully made it's series relevant again, and even gave it soft reboot if you will, despite being direct sequel to Rondo (which is a far better game don't @ me). But it's not some sort of grand revolution worth creating a genre over. Stop putting this game on such a pedestal, making people like me infinitely confused. And the thing is, I don't even think that Super Metroid is some flawless masterpiece. To make even more people mad, some future Metroid games are far better, I have zero nostalgia for either series. I just don't agree with this idea that SOTN is the game of similar quality which rivals it: it's a game focused on completely different thing, making it way worse in some of the most basic shit (like movement) and better in a lot more smaller details (the theme, style, animations, secrets, hotter protag etc.etc.)
Here's my rant. I don't know what I'm saying, I can't write. I just hope that it's not a peak of Castlevania games, because it's too damn fucking shallow to be one.