Actually, the "how dare you label me a heterosexual woman I'm just a woman" *would* have been a common reaction in the 1970s. And for the same reason. What the label does is to remind people the are not "the norm". You get a similar reaction with the word "bias", a perfectly normal, neutral word to thee and me but "I'm not biased! I'm middle of the road!"


My only issue with cis is that I am not sure it does apply to me and while I don't mind it for the purposes of group experience (ie I mostly experience life as a cis woman and have the privilege that goes with that) I would mind it very much if someone I knew well used it to identify me.