I don't think that's necessarily what it's about. It's often the case in long-running fandoms that new fans will have theories or headcanons that run contrary to the established "view," so to speak, which can lead to clashes between newer and older fans. Sometimes, this takes the form of older fans being assholes to newer fans; sometimes, it happens the other way around.

On Tumblr in particular, it's not unusual for newer, younger fans to feel that online fandom is their space, and that older fans are not only wrong, but that they've also "aged out" of fandom, have become creepy, and need to leave.

I could see OP referencing that phenomenon rather than, say, the modern updates to DnD.