Controversial take perhaps, but most of the N64 generation.

There are a few standout games that I think of fondly, but that was the generation where most developers were still trying to figure out 3D gameplay. Most games were clunky, where playing felt more like fighting against the mechanics rather than working within them. And they aren't that pretty to look at.

I also don't feel any nostalgia when looking at modern games that use that sort of visual aesthetic either. I am fine with pixel art games which emulate earlier generations, because the developers are (mostly) still taking that visual medium and elevating it above what technology was capable at the time, and the end result feels artistic and cool to look at. But games that emulate the early 3D art style are emulating the weird aliasing, melty and inconsistent textures, chunky models, etc. which is just taking the current medium and reducing it down to its worst state.