If AI art generartors are "a new form of self-expression", then why is there such prevalence of AI porn in the style of their source cartoon that people would only know were from separate artists from the Patreon URL in the corner?

If AI art generartors are "a new form of self-expression", then why is there such prevalence of AI porn in the style of their source cartoon that people would only know were from separate artists from the Patreon URL in the corner?