Higher resolutions IMO are not about the models themselves, but the edges of them.

A character model can look decent in 1080p, but the edges of the model in front of the background will be jaggy. Various anti-aliasing techniques can only do so much.

Besides, I know I'm more interested in higher frame rates. I'd rather do 1440p @ 144 hz than 4K @ 60 hz.

And I don't think there are even any 8K monitors out yet.

The 8k is really just a sneak peek at the future. I doubt anyone will actually be expecting to game on that resolution this generation.

It's not always about providing the final product in 8K - 8K means you can have multiple 4K windows up.