100% of transgender women are biologically male.
That is the concept to really grasp, in order to fully see the picture.
Transgender women have their own issues, and should of course be protected from harm. But they are not the same as females.
Females have their own needs, including healthcare, spaces, representation, and identity.
You can sneer at the women who recognize that fact. You can dismiss the wisdom and experience of the feminists who have been tirelessly working to protect women from sex-based violence and oppression. You can smear all the journalists at the Daily Mail, Spectator, and the Times and consider the readers of these publications as "less than." You can pretend vulnerable female prisoners don't matter, maybe because you think you'll never end up there. You can call other women hateful witches and join in the calls for persecution of wrongthink, because you think you're more "enlightened" than they are. You can dismiss religious women as "crazy." You can think you're better than other women, smarter, and more caring.
You can dismiss all the women on this board, who have been thinking, speaking, and researching this issue for a VERY long time. I am but a newbie, but radical feminists probably know more than most people in this "debate," because they don't really care too much about Judith Butler and the theoretical existence of a million gender identities. They don't get bogged down by whether someone is neutrois or agender or gender-fluid or non-binary or what. Radical feminists care about female bodies, power dynamics between the sexes, male violence, and the real lives of females (as a group based on shared biological traits) which are shaped by one's sex observed at birth. That would include transgender men, also, if trans men wanted to be part of such a feminist movement.
When you actually dismiss the women who are worried:
You are choosing to side with the males who say they are women, instead of with actual females.
That isn't feminism.