This isn’t a completely subjective question like “what’s your favorite color”, though. The question specifically is which characters are better than other characters when two equal opponents play at some specified skill level (usually in tier lists it’s assumed that the skill level is “good” or “great”, somewhere along those lines). There’s some subjectivity in there, yes, but also quite a bit of objectivity (comparing poke speeds, hitboxes, damage potential, etc.)
It’s as if I were to say, hey, I think the Detroit Lions would beat the Steelers 8 times if they played 10 games. Most everyone who follows football would disagree with me, and rejecting their arguments as just being “popular opinion” isn’t going to cut it, because there are clear indicators (win-loss record being one) that what I’m saying is faulty.
The consensus is that Ken beats Honda and this has usually played itself out in tournament play. Saying that your Honda “does fairly well against good Guiles and especially Kens” isn’t convincing unless you have some evidence that your conception of a “good Ken” is equivalent to or better than the people that you’re arguing against. Either you play them yourself and prove your point or you point them out to a Ken that you’ve beaten and have them play that guy - if that Ken turns out to do well against them, then you have evidence for your argument by proxy.
Alternately, you can describe your strategies against Ken and point out why Ken’s responses are unsatisfactory. Or why the changes in HD Remix substantially change the fight. This might turn into a bunch of theory fighter but at least you’re giving some backing behind your statement.
Bird and Jordan talked some MAD shit back in the day. It’s not a nice thing to do, but what does it have to do with people’s skills?
As for the “community knowledge”… there’s a lot of it, but it is scattered here and there throughout several long threads so it’s a bit cumbersome to search for. But it does exist.