Anything from saying there are 2 genders, saying what defines a man or woman is biological sex, or anything that goes against trans rhetoric. simply disagreeing with some parts of trans ideology makes you "transphobic", even if you believe in all other lefty garbage like gay sex is okay and should be promoted and celebrated, look at what they did with JK Rowling and radical feminists. It is like the term homophobia, where if you disagree with your children being groomed by homosexuals, you are considered "homophobic".