Let me be clear - male bodied person decides they would be more comfortable presenting "as a woman". 99% of the time I have no problem with this. I would not want them to lose their job as, say, an accountant as a result. I would not want their landlord to evict them as a result. I most certainly would not want them to be subject to abuse on the street as a result. I would politely call them by their chosen name and even pronouns (though I draw the line at legally enforced pronouns - I am not prepared, ever, to refer to Lisa Hauxwell, Davina Ayrton, Karen White, etc. as "she").
However, 1% of the time...
No to male-bodied rapists (indeed any male bodied prisoner, even if it's only for, say, embezzlement) in women's prisons. I'll join in a campaign for specialist trans wings, no problem there.
No to male-bodied patients on closed psychiatric wards with vulnerable women.
No to male-bodied individuals in women's competitive sports. I'll join in a campaign for men's sport to be more inclusive of gender-non-conforming individuals.
Individual women to have the right of veto on male-bodied HCPs providing them with smears or breast exams.
Women to have the right to set up women-only services if they want to. (So, by all means set up a trans inclusive rape crisis centre - but do not set up a legal framework which makes it illegal for a group of women to set up a women-only rape crisis centre if they identify a need for one).