I already mostly ignore new recorded music because of this problem.
An AI detector (if it were reliable) would at least help with that issue.
But this is only about machine-generated works that are trying to pass as human works. If machine-generated works don't do that -- if they become their own kind of genre -- that's an entirely different thing.
But by "machine-generated" don't you mean "text that came out of an AI model"? My argument in the post is that such output tells us very little about how much human input went into the original work. It's all lumped together as AI slop.
You are correct that "AI detectors" (if they were accurate) give a very crude indication and omit nuance. That sucks. But, from my point of view with creative works, such a thing would be better than nothing.
At least if there were such a detector, then there would be a way that I could be comfortable with at least some new works. That would be an improvement over the current state of things, where my default position has to be to ignore new works altogether.
My biggest issue with AI text is just that it's annoying to read, so I get put off before I can figure out if the content is actually worth reading. I would love a detector that detects the style of writing I find annoying and warns me, or offers to rewrite it so I can give it a chance at least.