Good game, overall. Way easier than any of the other games, so it'd be a good introduction into the series for any newcomers. Solid, simple, and playable.

But it's not without its problems. It was very short and didn't feel too difficult: about halfway through the game, I had infinite healing items (because you can just stockpile them). The boss layout was kind of terrible: it feels like you're probably supposed to play every world's levels at the same time (e.g., 1-1, 2-1, 3-1, etc.), but I played each world as far as I could get it and by the time I got to worlds 4 & 5 the first bosses weren't even really a fight. I got way overleveled for the area and trashed on them: not bad, but not challenging. And speaking of...

Let's talk bosses for a minute: low-key kind of terrible, honestly. Out of all of the bosses (of which there are only a few), half of them I did on my first try. Maybe it's because I've played several the other Souls games before, extensively, but that wasn't a real challenge. Also, 6 or so bosses were gimmick fights without a challenge other than figuring out what the gimmick was. The easy gimmicks? First try on the boss, and an easy win. For the difficult gimmicks? It takes a lot more work, which ended up becoming mindless tries and runbacks. Dumb, stupid, bad boss designs.
But the few remaining bosses were cool.

All in all, I'd recommend this as an intro game or as a little palate cleanser from the actually difficult games in the series. I myself played it in between a couple of narrative-heavy games, and it did the trick. It's pretty to look at, it has good vibes, the world is interesting (if not terribly fleshed-out to a surface-level player), and it's fun enough. I am glad that it only took 16 hours for one playthrough, though, as I wouldn't want to be stuck in this game for the 35 hours that Dark Souls 1 took.
Pretty great for what it is, though "what it is" is more of a tech demo for what the future games could be.

Poor Demon's Souls. You walked so that Dark Souls could run.

Pretty incredible, all told. Definitely worth playing if you enjoyed 2018.

I didn't personally find the ending setpiece all that great, and I didn't understand the ending itself (I had to go online to look up what the details happening meant). Maybe I'm dumb and missed the subtle hints? But I could've done with about two lines of dialogue, at least giving me a hint as to what I should've been focusing on.

Still, now that I understand, it's a great game. Slightly better gameplay than 2018, slightly worse story (in my opinion), definitely worth a second playthrough in a couple of years.