I think you're confusing, in some cases, fans of specific cult films with fans of specific directors.Quoting Israfel the Black (view post)
That is, mistakenly believing the people loved Fight Club because of Fincher and not because its subject matter hit a cultural nerve or because of Palaniuk's twisty story. (Somehow I doubt this subset of fans were eagerly awaiting The Game when it hit theaters or running to Blockbuster to rent Alien 3. For one, they were to busy punching each other in crab grass filled backyards, much to the delight of local news crews across the country).
It's similar, to me, as universally conflating Star Wars fans with George fanboys. Or thinking that everyone who loves Indiana Jones rabidly follows the career of Steven Spielberg.
I say Soderburgh disappeared for 10 years because he pretty much did. From 89 to 98 he made a string of movies that nobody saw. His career, and his name, had faded from public view when he came out with The Limey and Out of Sight at the end of the 90s.
I say he's more mainstream because he doesn't do small art house stuff like Punch Drunk Love. He does big budget studio Oscar bait crammed with A-listers and in between experiments with the commercial market. He's also, afaik, the only one who has done multiple sequels to his own work, which is a huge indicator as to where his interests lie. (And no, you don't get to sneak in Nolan. Without one of the biggest, most famous franchises in the world, Nolan would be a footnote in an Intro to American Independent Film textbook at a community college.)
While Soderburgh had a 10 year head start on the other guys, he's also made 3 times as many movies, and produced nearly a dozen others. By comparison, Anderson has made what? Six? Fincher about the same? They're a lot more careful about the stuff they put out there.
I call them artistically rigid because I can almost guarantee you these guys will rarely, if ever, deviate from their established styles and fields of interest (can you imagine Taantino attempting something like Age of Innocence or Kundun?).
Their work has become so codified they operate almost like their own brands, like Woody Allen does and Martin Scorcese and Spike Lee used to.