Yeah that's a good point.
In the specific case of Ready Player One, I think there's an aspect of conquest there. A book aimed at "our" subculture being made into a movie is good because it shows that "our" subculture is getting some notice. That book being made into a huge Hollywood movie directed by the biggest-name film superstar director of all time, proves that "we" won the culture war. "Our" subculture has conquered the mainstream.
Critically, though, it's still a subculture. A lot of nerds got really annoyed by the way that the Marvel superhero movies invited everyone in and made superheroes just another part of the mainstream. Superhero movies weren't just for "us" any more. By contrast, Ready Player One is very definitely not trying to invite everyone in. It remains a subculture film, just one that elevates that subculture above the mainstream.
I hadn't considered it before, but I wonder if this means that the reference-heavy nature of Ready Player One can be understood as gatekeeping to prevent absorption by the mainstream? A gamergate sort of thing?