Your argument is somewhat tangential - are you arguing women are defined by their ability to give birth? Seems fairly obvious that doesn't hold up even when we aren't talking about trans people
Some of the more extreme trans activists seem to want to pretend that these clusters don't exist, which puts them at odds with reality.
Other seem to demand that the clusters shouldn't matter, which I find rather optimistic since they're relevant for reproduction.
Trans rights are a noble goal, but some of the statements made by trans activists are a bit out there.