Because it literally is. If you knew the exact terms to get the the AI to recreate something in its training data, it could, 1:1. And if you ask it to create you something new, no matter what parameters you use it will look like a mess of garbage data. Generative AI is literally just art laundering just like how Language Models are writing laundering. We tend to use humanizing language but ultimately it's a machine which uses a bunch of dials and levers to determine how much % a work should resemble one piece in its training at a particular point of the work and how much it should resemble another in another. There's a reason why a lot of modern image bots have literal fucking watermarks all over their outputs. Because the images were flat out stolen.

The tech itself is pretty neat, you're essentially making a virtual brain and having it do useful work, but ultimately all the capitalists running these tools see it as is another method to bring the public under their exclusive and totalitarian control. We could have had a cool roboartist putting out new and unique works but instead we get people losing their job because an inept system hyped up by silicon valley fart huffers claimed it could do their work for free and it only gets worse as these AIs use their own garbage outputs as training data.