story
Higher compression means longer load times, so there's incentive to not compress more than absolutely necessary, and the biggest games tend to have huge worlds, which means you can't hold the whole world in memory at once. So you have to stream it in.
It's a constant balancing act between your nominal hardware target, the space the game will take up, up-front load times, and the amount of stuff that can be in a scene before the hardware can't keep up and you get model/texture streaming pop-in, stuttering, or an otherwise degraded player experience.
Perhaps in the next few years we'll see games leveraging super-resolution AI to quickly produce usably high-res textures from lower-res installed ones in storage faster than a directly compressed equivalent could be.... or games will leverage the same to take what they already ship and make it even higher detail...
I mean, you could make a modern open-world game where all the textures are procedurally generated from set formulae, ala https://en.wikipedia.org/wiki/.kkrieger .
It might even load quickly, if the texture generation algorithms were themselves parallelized as compute shaders.
But it'd be a 100% different approach to an art pipeline, one where you can't just throw industry artists/designers at the problem of "adding content" to your world, but instead have to essentially hire mathematicians (sort of like Pixar does when they're building something new.) Costly!
In fact, games are one of the few areas where all those compute/storage resources in private PCs are mostly justified.
