In my opinion the biggest problem with fandom is that it leads to an overly attached attitude towards some work and creates a sense of entitlement and audience

In my opinion the biggest problem with fandom is that it leads to an overly attached attitude towards some work and creates a sense of entitlement and audience capture. Fanservice is a very close cousin to fandom and for very obvious reason, a lot of media with huge fandoms end up being driven by serving people the same thing over and over again because creators lose the ability to actually challenge their audience. It's how you get the whole Marvel industrial complex. I've always liked Nabokov's attitude towards reading: "A wise reader reads the book of genius not with his heart, not so much with his brain, but with his spine. It is there that occurs the telltale tingle even though we must keep a little aloof, a little detached when reading." Fandom is the opposite of this where people end up treating their favorite media the way K-Pop fans treat K-Pop idols and it's why fandom driven media just ends up lowbrow and bad.