"That rubs people the wrong way here, even when my intention is to save someone else the legwork of either looking something up or explaining something to someone else. And it's always something stupid, like trying to say durability matters in a rain shell (Hiss! Heretic!)"
Perhaps I can offer a different perspective that you might find useful, or not. In my opinion, very, very few people take issue with what you have to say in these forums. Very, very few people have any issues with being disagreed with. You've played the victim card a few times here already and claim groupthink by others, yet I can't think of a thread I've read where everyone agreed with everyone else. Lots of disagreements on this forum, and you're not picked on for disagreeing. And my word, you're not a scapegoat for anything (not even sure where that one came from).
Some of what you feel on being attacked is really just good natured ribbing - you seem to have a pretty thin skin (this is all my opinion). But I think that most of the negativity from others has nothing to do with what you say, and everything to do with how you say it.
In the short time you've been on these forums, you've started threads and then gotten pissy when people didn't abide by your specific rules when replying; you've told someone about twice your age how they should behave/respond/act; while you don't mind disagreeing with others you don't appreciate people disagreeing with you; and you whine (yes, whine) about how mean some of us are and how under appreciated you are. You also seem to think your opinion is just correct and should kinda be equated to fact.
Even your example above illustrates this: you're not saving someone else the legwork of looking something up or explaining something to someone by saying durability matters in a rain shell. There's no fact in that at all - durability will matter to some and it won't matter to others. It's opinion. And there will be varied opinion on that, just like everything else here.
You just don't seem to realize that (again, in my opinion), too many of your posts simply come off as patronizing, arrogant and pompous. Of course people are going to poke fun and react negatively to that. Many of the folks on this forum have lived significantly more life than you, not to mention have significantly more backpacking experience than you. So when all of your 23 years comes bouncing Tigger-like onto the forums to show us the truth, the way and the light, well, many of us just roll our eyes, and some of us negative nancies just smile and poke poor little Tigger.
If you fail to see or can't admit that you contribute to this problem/issue, then I guess there's not much more I could say. But I'd recommend truly thinking about how you might be coming across to others instead of simply blaming the way people respond to you solely on them.
Lastly, I think 'smug' would have been a much better word choice than 'glee,' but that's just me.