I love Morrowind so much that I refuse to admit to its ugliness. I will choose to believe that the less-than-perfect graphics simply enhance the alien look and feel.
My mommy group had a minecraft server when all our kids were potato stage and it was mostly a few very talented redstone builders, a few people collecting resources, and my husband in the corner building a penis castle with penis fountains overlooking our little town.
hahaha I am actually glad that it doesnt look polished, but still looks good enough. This way you can make it much prettier with mods, but if you have a slow pc you can also enjoy playing it without much trouble!
Hot take: nethack with tile sets is uglier than nethack without the tilesets. At least the ascii characters are interesting! Either way. I love nethack.
I assume we are only talking about games that looked ugly pretty much upon release, and not games that look really bad now but are still really fun.
In that case starting with the most recent:
Save Room - Puzzle game that is just the inventory management from survival horrors like Resident Evil. Might be just a simple joke game, but I had a lot of fun with it.
Outcast - The voxel tech just wasn't ready. Amazing game, one of the best of the era, but it its visuals left a lot to be desired. Modern updates have greatly improved its look.
Eradicator - This one was looking out of date when it came out, but its a surprisingly awesome and deep 90's era shooter.
Beauty is, I think, somewhat in the eye of the beholder. A few games that couldn't have been called very conventionally pretty, though:
A number of roguelikes that use ASCII graphics (though today I play Cataclysm: Dark Days Ahead* in graphics mode). Same for Dwarf Fortress. Often these are very deep games with a lot of gameplay to explore and a lot of replayability but nobody is playing them because of their graphical beauty.
The Dominions series and Conquest of Elysium series from Illwinter are fairly-involved strategy games, which both have graphics that...well, I can understand someone appreciating some aspects of them, but again, nobody is buying these games for the graphics.
Kenshi -- a squad-based open-world sandbox game -- has a certain amount of attractiveness, but the textures and models are limited in detail and I don't think that people are going to call its graphics beautiful or on-par with high-budget games today.
Noita is a difficult action roguelite game where one constructs wands using various spells and spell modifiers and gives one's wizards various powers as they dig through a world. The graphics are pretty chunky pixel stuff, which someone can enjoy but aren't something that you'd probably play the game just to look at.
I think that the importance of graphics is more-important for games that don't have a lot of replayability. There's a lot of "oh, wow" factor when you see something beautiful and it's still novel. But if you see something many, many times, eh, less-impressive. A lot of roguelikes and roguelites focus on replayability -- the graphics of something that you've seen countless times are going to be old hat at some point, no matter how pretty.
I loved hogs of war as a kid. I think they did what they could with the limitations of the time. There was a ton of voice acting in that game and that's probably what ate up the disk size.
Did the devs just take a boat load of acid while making this game? The top down view looks pretty good, but the character dialogue (I think?) screen looks like it's A.I generated before A.I Generation was a thing.