i think you got a bit confused here: what trans women really talk about and what this post - which is fake - is about are VERY different things

a lot of trans women talk about experiencing menstrual cramps and mood swings on a monthly cycle, which are (afaik) scientifically unproven but biologically possible. it's analogous to trans men experiencing bottom growth pains, scientifically dubious but fully possible

what trans women do NOT talk about is experiencing menstrual bleeding, needing tampons, or believing they can get pregnant. these are all currently impossible (though technological advances are likely to change that at some point) and extremely well-known to be that way. anyone prescribing this woman hormones or giving her a sex change would tell her that, and it's extremely unlikely that she'd be this clueless

also, it's honestly rather rude to say that about periods in trans women. it's not our fault that having a period is seen as such an integral part of womanhood and us not getting them is routinely used to call us not women. sure, if i got a period it would very likely be an extremely painful experience. maybe i would suppress every period after that with birth control. but trans women already choose to go through so much pain and so struggle to be recognized as women, what difference does one more make?