Do you really, really think that his fan base really, really cares who he does a film with?
Quick, do you think his fan base can actually name the last three producers he worked for?
Directors are quite a bit more visible, especially someone like Mel. FWIW, off the top of my head Nolan, Mendes and Scorsese.
I think his fanbase is changing quite a bit. I know a lot of guys who used to dislike him, but have come around recently.