The first time I heard the term ‘cisgender’ it was in a safe sex brochure. I asked the person at the info table, where I had gotten the brochure, and they had no idea either. I tried to look it up online, and couldn’t find the term. I think because the word is pronounced “Siss-Gender” it sounds like sissy. That might offend some people? (particulary men with internalized homophobia or misogyny). Perhaps they think they are just ”people” and only trans people should be labeled?