My privilege as a straight, white, cisgender, middle class thin male

[Esquilax]

I don't really get your point. Of course politeness is limited on my willingness to extend it to others. That is all that it really is. I'm not willing to be sensitive to people's made up gender identities, more of which magically crop up everyday. I find it to be stupid. If someone tells me they are bicisflogendered, I will probably just ignore it and make fun of them later. Luckily online you can just make fun of it right away, because it's dumb.

Of course your specific politeness is limited by you, but in general, what is and is not polite is not determined solely by you; just stating your unwillingness to participate in the acceptance of others doesn't absolve you from being labelled impolite or dickish over it. And, well, if you're making fun of people behind their backs over their labeling choices, that is kinda dickish.

In the end, regardless of how pretentious or manufactured you happen to think it is, all these sexual and gender orientations are are labels made to describe what a person is with more specificity, and I don't think it's too much to ask that they not be treated differently because of that. You may think it's dumb, but all you're really doing is making fun of something that has always existed, but only recently got a name.

As to being sensitive to them, what's actually being asked of you? Beyond "be a normal person to me," what great feat of social largesse are you being asked to commit?