Really, this is between 4 and 4.5 stars for me. Pretend it's 4.2. Ratings are arbitrary, who cares?
You can basically copy over the stuff I said about gameplay, atmosphere, and structure from my review of Metro 2033 Redux. I could Ctrl-C and Ctrl-V, but that would be a waste of bandwidth.
But the STORY, dear God, the STORY makes 2033 feel like mere groundwork for this. The first game, if you recall, was a simple "deliver X to Y, and Z, A, B, C, etc. happens inbetween" structure. At the end of that game though, the Dark Ones are annihilated. Except they aren't. There's a Dark One that's only a kid that the weird mystic I didn't mention in the Metro 2033 review due to lack of space wants you to make contact with. Meanwhile, D6, the wacky secret Soviet bunker (they must make them by the dozen!) is preparing for a possible Hoover Dam from Fallout New Vegas type scenario. But ALSO, a traitorous ex-Ranger is delivering a mysterious container to the Communists. There's also a hinted love interest for Artyom thrown in for good measure. He deserves it, I'd say.
The interlocking nature of all these narratives, and the overarching mystery, makes for better setpieces than the first game, in my reckoning, and in these first two games, it's all about linear setpieces. The environment design is also as good as the first, if not slightly better, given there's a Super Mario 64 style endless oneiric hallway near the end. I won't spoil the context. In short, 4A does it again, although I'm confident the next game will kick my brain in the ass, still, comparatively speaking.

In the middle of the development of the first S.T.A.L.K.E.R. game, a few crucial creatives started 4A Games in Kyiv. They weren't the first studio to schism from GSC Game World, and they weren't the last, (because, it seems, Sergiy Grygorovych is a donkey), but by now it seems 4A has taken the prize as the chosen spiritual successor studio for the S.T.A.L.K.E.R. lineage or whatever, even though S.T.A.L.K.E.R. 2 is coming.
I have never played S.T.A.L.K.E.R. (I'm getting sick of typing that out, there's so many punctuation marks), but I am given to understand it has this gameplay/vibe, just more open-ended. And by this gameplay/vibe, I guess I mean the Big Roadside Picnic Energy game. You know what I mean; post-disaster- no apocalypse necessary, but it's preferred; an overwhelming Slavic atmosphere that if I could pin it down is somewhere between pure dread and dogged determination in the face of increasingly long odds; uncanny monsters and anomalies. You know it when you see it.
Although this game has certain kinks added to that formula, probably from the source material. Both Communists (not the cool type, the Marxist-Leninist type) and Nazis (there is no cool type of Nazi) are besetting the poor bastards who are just trying to survive. Most iconically, bullets are currency, although specifically high-quality bullets. The cheaper, post-collapse-of-all-professional-munitions-manufacture pills are worth nothing, which makes sense.
Mechanically, the game is sound. Before it was remastered it was probably less sound, but as of right now, the game is sound. There are often, throughout the extremely linear campaign(which is to its benefit, given the subway theming, because mission by mission, on the loading screens you see your particular route through the titular Moscow Metro), moments where stealth is incentivized, although not mandatory, and this probably lends it some replayability, alongside the generous difficulty options. The real thing that makes this game special is the atmosphere and the tension; at any moment, you feel like, you could end up in a dangerous tangent, whether it's the enemies cornering you in a cell and then pulling a trigger in your head, or the monsters killing you, or the weird alien fellas killing you. It all boils down to feeling like time is running out, basically.
That's due to the linearity to a great extent, but it's also due to the story; you are a 24-year-old guy in Exhibition who has up to this moment been your average survivor. Orphaned, yes. Living on a knife's edge, yes, like everyone in this hell the world has become, but so far not slipping off. Anyway, the station gets attacked, and you're forced to get help in Polis from a faction of good guys. That's a simple premise, but the trick is in the experience, the moving on down the line (and above the surface, God help you), the forward momentum, the world that is constructed around you by the developers. Even in this sort of jank state, the developers show a great understanding of narrative and environmental design (the latter looking better in this remastered state than it did before, probably). This was a wild ride, and I am dying to know how they improve on it with the other two games.

This is a good game, but there's far too much of it. If I had taken a week or a bit more than a week to concentrate my gaming activity to only playing this game, I'd have probably been dead by hour 20. I can't tell you of what; probably acute nicotine poisoning, given the subject matter of this game.
Oh, the story? Who gives a fuck? I am not the sort of gamer that has to have every story in their games be good- and at least this one didn't actively anger me like Far Cry 5's did. The villain was stunt casted. There's a Rambo mission. They hath given me slop, and I have eaten, and yea, I have not vomited. I can't say that with every game like this. Give me a break.