We're talking about entertainment products. What do you think it would be like to be the only Star Trek fan in 80s Mongolia? I think it would be pretty sad. Yes, the show would still be the same, still be as good, but you have no one to share it with. They simply don't get it.
So even the most hardcore nerds adapt their tastes to what other people like. It's not so hard, because hey, there are other good TV shows, there's other reasonable entertainment. It's hard to say objectively that a Star Trek convention is better than a Mongolian Chess tournament anyway.
But when advertising comes into the picture... It's not that you necessarily think the Marvel Cinematic Universe is the best thing ever. It's that you know everyone will be talking about it, everyone will be referencing it, so if you can find at least decently entertaining you should maybe prioritize getting into that over getting into Danish underground comics from the 90s.