Instead of saying "Cis is meaningless/Cis is silencing" or whatever, say something along the lines of:

"Please don't call me cis, cis means 'someone who identifies with their assigned gender' and that doesn't describe me."

"I don't identify as cisgender because gender isn't something I personally experience"

"I don't consider myself to have a gender identity, therefore I'm not cisgender"

This has worked for me EVERY SINGLE TIME I've used it in TRA/leftist heavy places. Usually after I say something as vague as "I don't identify with that, please don't call me it", they shut up, because they believe that all "identities" need to be put on pedestals and protected. As long as you don't go into detail about why you reject "cis" they should be fine with it, lol.

Lol, I might give this a try and see how it goes. Sometimes people are remarkably persistent in asking questions; but some might not out of fear they might "out a trans person in the closet."

but one thing they DO care about is using us to justify concepts like "nonbinary" while they try to paint us as "freaky third sex people." So often, even saying "I'm intersex so I'm not cisgender" is enough for them to not question my "identity."

Small silver linings?

And as a bonus; you may also be able to find like-minded people by looking closely at who does similar things.

Ahh, that's a good point. All right, I'll give it a shot.