Well my school was particularly infamous for its cliques and bullying, it was not a friendly place for individual points of view, even among the teachers, hehe.
Yeah, that's unfortunately a large fact in the reason why older, not as "cool" things aren't more popular. If the popular kids deem it "uncool" then kids wont bother mentioning it. Lucky for me I had a good group of friends growing up, so when we discovered things we adored (LotR, Newsies, X-men, Twin Peaks, etc.) and we'd run around the playground shouting our love of said things, we may have gotten weird looks and gotten called names, but we had each other and that's all that mattered. I'm also blessed to have gone to a single gendered school. Yeah, there were cliques, but no one clique was really more popular than the others, so no one really cared what the other cliques were into.
I just wish bullying wasn't such an issue. Kids should be able to voice/express whatever it is they love.