Here's an 11 year old video trying to educate people who think they "hate CGI" just how much CGI they've been watching, just without realizing it, because it was actually quite good: https://www.youtube.com/watch?v=bL6hp8BKB24

We are almost certainly already there with AI coding, and if we aren't I give it six months to a year tops. AI is being used for coding everywhere now. The difference between the slop and non-slop isn't whether or not AI is being used. It's how much care is being taken by the developer. But it's no longer a question of whether new code had AI contributions. It did.

By the simple mechanics of information theory, there's always going to be certain common grain to what you get if you try to prompt entire massive systems into existence with minimal human input as to what the system should be. You'll always be able to type in "give me a 2D platformer like Mario but with cats and barn animals instead" and get some sort of slop result, no matter how good that slop result may eventually become in the abstract. It'll take more information from somewhere to make it something other than that slop result.

(Though that information may not all source from a human sitting there and batting things back and forth with an AI, though that will be an effective method.)

I'm confining myself to "code" here, which is mostly useful to a game because of the results of the code. Gamers do not sit there and actually admire the cleverness or cleanliness of the code. I'm not speaking to art, which is a more complicated scenario. You can make a similar case for visual and audio art, but I also don't think the AI stuff is as far along relatively speaking as it is for code.