In fact it would be impossible to do what you suggest, because the ways in which people want to be respected could be (and often have been) incompatible. For example, what if two people with different religions both want to be treated as believers in the one true religion?
There are also plenty of individual cases we'd both find hard to swallow. Murderers who wanted to be regarded as upstanding people, and so on.
(And "who" in this case is much stronger. "Whom" introduces a jarringly pedantic note.)
But you could treat them as your equal until they do something to show they're not your equal, which is mostly what PC should be about.
Don't reduce people to a single defining characteristic, because that makes it easy to write them off.
And I nowhere compared the two cases you mention. (That was an extreme case of putting words into one's mouth even for HN.) You're acting as if I said for ∀x-P(x) when in fact it's pretty clear I said -∀xP(x).
I'm done with this conversation, incidentally. I find that threads in which I have to say "no, what I said was" to this extent are always irrecoverable.
For example, many people are great or okay at their professions - but not all of them. There are respectable and respected doctors, and there are those that just have a degree and a practice.
Quite a few people have made unacceptable moral choices in politics, business or personal issues - and it's okay to disrespect them because of that, and publicly despise and shame those choices, no matter how it hurts their feelings and dignity. Respect honors people by drawing a line, by distinguishing them from the others you don't respect.
And by the way, wordsmith, it's "the fashions are in whom you're supposed to respect."