Yeah, I think it is mostly cis women who start to get territorial about speaking on womanhood in this way. It’s like they feel betrayed by transmasculine folks or something when its really not their place to feel betrayed! Its been interesting to be someone who is often perceived as a trans man by ultimately well meaning cis women in feminist circles. They will jump to exclude me from discussion about femininity and female experiences unless I make it clear that I identify as a woman. That usually makes them feel pretty bad, hah. Even then, mixed results at best. I have tried to be understanding in these situations.