"They" are the anti-AI mob. Like the anti-woke mob, but for artificial intelligence instead of non-white people and women. Same idea, different target.
Your analogy doesn't make any sense. You know when something's made by Nintendo, because Nintendo makes it. For all you know, they use AI, but since they're not bound by Valve's stupid rules you would never have any idea. Why would Steam take away reviews? Just because some people misuse it doesn't mean there would be a blanket removal. That sounds like you're arguing for my case actually: just because there are some bad actors, it doesn't mean you hate the system used by the actors.
It should be disclosed transparently and then people should judge themselves.
Then where do you draw the line? Should they disclose if women worked on a game? Men? Trans? Non-binary? Should they disclose whether they used Windows? Linux? Mac? Should they disclose whether they used markers or paint for their concept art? Some people hate each of those things listed, so you think we should enable discrimination against them, too, by requiring disclosure so people can make their own decisions?