As someone who has never played another Metal Gear game, I found myself hooked by the systemic stealth on offer. Infiltrating bases, taking out guards one by one, that stuff is catnip to me. There's also a busy story and boss fights which don't seem bad, but are not why I came to this game. I was more than willing to put up with those interruptions in a very satisfying loop.
My main complaint with this game is that the story line that Kojima Productions was so known for was underwhelming and had high points too spread out or prematurely introduced. With that being said, this is on a technical aspect alone the greatest stealth game ever made. And for me personally at this point in time, it is the greatest stealth game I've played and it may not be topped soon or ever.
The game is kind of an unfinished mess. The story sucks, the characters are inconsistent, Big Boss is barely a character, shit tons of filler missions, the story especially in chapter 2 is just made up of moments, there is no cohesive plot however im not gonna lie i still thoroughly enjoy this game cos for the first time in a metal gear game none of this shit actually matters cos the gameplay is where its at, phantom pain offers up these massive sandboxes with every imaginable tool at your disposal, you are given so many ways to approach missions. You can impersonate a woman, you can shoot your hand off, you can rescue animals and make a zoo, you can plant C4 on a dudes ass, wait for him to get in a chopper and then blow him up, Theres simply no end to the freedom you are given. A true masterpiece of gameplay design.