The problem isn't the new technology being easier to "fake" the art. Concerns about some art being "fake" because it uses technology is just a weird form of artistic elitism: new, therefore bad. I, personally, have no problem with people using AI art (unless they're using it just to trace over other people's work, which is wrong).
My main concern is one of curation and discovery. The Internet already does a pretty bad job of these. And as a result it is very difficult for new artists to be discovered and find any sort of audience. But now you have a force multiplier that specifically allows people to produce plausible, trend-forward, but not boundary-pushing art with no effort. And you can churn out hundreds of these per day to completely corner public art spaces.
The downside of this is that the AI is statistics-driven, so it's going to reinforce a lot of the trends of "mainstream" art. Think about how a lot of AI art trends towards this kind of realism-plus, overly cinematic look. Anyone not making that is going to be crushed by the trends.
Which of course is already a huge problem in music. "Pop songs" are a very rigid formula, like to the point where new hit music often comes with a flurry of lawsuits because it's difficult to actually create legally distinct work in this genre. The reason why music works this way is that the people running these companies have the same mentality as the hustlegrind idiots telling you to go spam poster sites with AI art. They are not creating art to communicate, they are creating art to fill a market demand.
So my concern is the "popification" of art, writing, and code, as all of that gets delegated to machines that are constantly reproducing whatever was popular back in 2021.