That's only true today. And it's quite difficult for artists by comparison. I don't think people will bother with the complexities of polygon based graphics once they no longer have to.
Not really. Look at how many calculations a single pixel needs in modern PBR pipelines just from shaders. And we're not even talking about the actual scene logic. A super-realistic recreation of reality will probably need a kind of learned, streaming compression that neural networks are naturally suited for.
They already are. But the future will probably not look like this if the current trend continues. It's just not efficient enough when you look at the whole design process.