Except… wide swaths of feminism still hate him for what he/she is. Because instead of being just a man, he/she is now a man refusing to adhere to the imposed rules of what women expect a man to be. So he/she is hated by them twice as virulently.
It’s why the term TERF - trans-exclusionary radical feminism - exists. Scratch the thin veneer of most feminists hard enough, and this can be found underneath in some capacity.
I really hope he/she has a strong support network in their friends and family members. They are going to need it.