> No-one is hiding information about their genitals by identifying as a particular gender. Don't make unwarranted assumptions and you won't have any problem. (That said, the false conception that trans people are tricksters lying in wait to ambush you with their unexpected genitals is a pretty big component of trans panic transphobia.)
It's not universal, but I've had conversations with quite a few trans people who considered it transphobic to care about genitals in dating.
That's just an anecdote, but as a more public example: consider that dating apps/websites let you select gender identity but don't have space for identifying physical sex characteristics, even though that is a primary selection criteria for many people. I consider this pretty ridiculous when a lot of these sites have a box for height/weight and even star sign.
> If you need to know about someone's genitals, you can just ask them before you meet them.
I think part of the problem is that you can't. There are lots of trans people that would be offended by such a question (and if they aren't, then why not just communicate it publicly in the first place!)
> the underlying reason behind all this is pregnancy and families, then there are questions you have to ask anyway. Not every cis man or woman is fertile or wishes to have children.
It's needn't be about pregnancy and families. It may simply be about attraction. For example, I'm attracted exclusively to biologically female people. I know from my past life experiences that this rule holds consistently, so if I'm looking for a sexual partner, then I don't want to waste my time making an emotional connection with someone who I then later find out isn't sexually compatible with me.