Agreed, though I think that spectator-sports-fandom (if that's what you meant) analogy also has emotional team-identification connotations that don't apply to the majority of HN strong opinions about browsers. (But apply more to, say, Emacs vs. Vim, or tabs vs. spaces.)

I think lot of the HN browsers strong opinions more akin to "Why do historians have strong opinions on geopolitical intrigue X" or "Why do doctors have strong opinions on the effectiveness of pharmaceutical Y". Strong opinions, because they are experts who care for important objective reasons.