While I understand their position, I disagree with it.
Training AI on copyrighted data - let’s take music for example - is no different to a kid at home listening to Beatles songs all day and using that as inspiration while learning how to write songs or play an instrument.
You cant copyright a style of music, a sound, or a song structure. As long as the AI isn’t just reproducing the copyrighted content “word for word”, I don’t see what the issue is.
Does the studio ghibli artist own that style of drawing? No, because you can’t own something like that. Others are free to draw whatever they want while replicating that style.