I think being a nerd requires being a bit socially clumsy about your interest, and talking or signalling about it in situations where most people don't expect it. So being a nerd about completely mainstream stuff like pop music or football is not possible, that's just fandom. Being a nerd about very well known and relatively well-respected stuff like classical music or birdwatching is rare, because most people who are classy enough to care about the thing in the first place are also classy enough to know when to shut up about it. But comics? Star trek? Power metal? They have fairly low barriers to entry *and* most people don't care about them, so there's plenty of opportunities to bring it up to people who don't want to hear about it.
So that's why I think nerdery usually attaches itself to the typical targets.
I think being a nerd requires being a bit socially clumsy about your interest, and talking or signalling about it in situations where most people don't expect it. So being a nerd about completely mainstream stuff like pop music or football is not possible, that's just fandom. Being a nerd about very well known and relatively well-respected stuff like classical music or birdwatching is rare, because most people who are classy enough to care about the thing in the first place are also classy enough to know when to shut up about it. But comics? Star trek? Power metal? They have fairly low barriers to entry *and* most people don't care about them, so there's plenty of opportunities to bring it up to people who don't want to hear about it.
So that's why I think nerdery usually attaches itself to the typical targets.