Sergio seems to think so. I'm not sure about that, but I do agree completely with this, from my co-teacher Amy Adler:
"One of the worries that I think we should all have about the extremely chaotic and uncertain area of fair use law is it will force artists to steer clear of engaging in work they should otherwise be able to do for fear of getting sued, and that applies to all artists rich or poor."
UPDATE: Sergio responds here. I'm still not convinced. What we haven't seen, I think, is a "reverse Cariou" -- that is, a case where a "rich" artist sues a "poor" appropriation artist and, unlike Cariou, wins. I agree with Sergio that what we have now is a clusterfuck. I just don't think it has much to do with the relative financial standing of the artists.
