>>23682703Commissions for art is harder to fake since they either have to commission tons of artists which stops being feasible in terms of time economy and just is a lot of work.
Typically fanart is done mostly in response to popularity (for clout) or by fans who are inspired or want to receive praise from the vtuber.
Fanart and fan content is objectively the best indicator of overall fan engagement. And there's no better engagement than wanting to fuck a girl.