I started this list as a semi-ranked list, but it just kind of fell apart as I remembered more titles ... lol ... anyways
God of War (PS4):
The most graphically breathtaking game I've played this generation
Uncharted 4 (PS4):
Best environments I've seen this generation.
Mario Kart 8 Deluxe (NS):
Still one of the most visually appealing games to my eyes. It's so crisp, so clean, you almost forget about the numerous technical limitations (and you would completely, if it wasn't for the video editor). This is the best looking 3D cartoony game I've seen.
Monster Hunter: World (PS4):
By no means as graphically impressive as a PS4 exclusive or the plethora of intensive PC games out there. Yet despite that, the amount of work put into the monsters is utterly astounding. I've loved the monster designs for the series since I first became acquainted with it on the 3DS with 4 Ultimate, but World is the game that I think truly proves the amount of artistry that's required to make fictitious creatures look like plausible entities. So much effort, and it all paid off, it's like porn for my imagination (Uh ... not that i'm into bestiality).
The Witcher 3 (PC):
I don't know, for my money, there's still not a lot of open world games that beat this from a graphical perspective ... could be objectively wrong, though. I just feel like the environments are so much more real than the alternatives on console. The game doesn't look that impressive on console nowadays, but on High/Ultra it still stands out fantastically.
Horizon: Zero Dawn (PS4):
People really underate this game's art style and design ... it's fucking fantastic. I like this for a lot of the same reasons I like MH:W graphically. They put so much work into making the animation of robotic monsters look like real living creatures while still maintaining that technological tone to their movements. There is a slightly soft, pleasant, cartoony nature to the game that is very understated, it adds a lot to the environments. Too bad they look quite plain in a lot of places ... with a game like MH:W you get the benefit of maps being very particular in their design, with Horizon they did a great job of making various regions feel different like they had a place in the world, but there's still a lot of areas that blend together.
Grand Theft Auto V (PC):
Shitty ass game ... good for benchmarks on PC though at high/ultra
Star Wars: Battlefront II (PC):
Really makes you really feel like Vader
The Legend of Zelda: Breath of the Wild (NS):
If it wasn't for the fact that some of the textures are extremely bland ... or that there is too much copy-pasting, this would be a lot higher. However, many open world games or even games that just have large map sizes still look like fucking trash even ten years after this kind of title got popularized. In that respect, Breath of the Wild is very impressive. It is one of the best games to get on a high mountain, look out into the distance, and imagine fields of green grass waiting for you to roll around in them.
Metal Gear Solid 3 Pachinko Machine Cutscenes (PM):
We passed upon the stair.
We spoke of was and when.
Although I wasn't there,
He said I was his friend.
Which came as some surprise,
I spoke into his eyes:
"I thought you died alone?
A long, long time ago ..."
Oh no, not me!
I never lost control.
You're face, to face...
With The Man Who Sold The World