Different people use different words about their transition, and I think you’re imposing your own experience onto others. To say that trans women categorically weren’t men in the past totally invalidates how I have always described my transition. I don’t share your experience, and I don’t describe my past self the way you seem to think I should.

I was comfortable with my gender, and I don’t think it was invalid for me to have identified as a boy. That’s not who I am now, but that doesn’t invalidate my identity for the first 16 years of my life. And I think if speaking, behaving, or filling the social role of a male doesn’t make it valid to say that I used to be a boy, then that feels invalidating to everything I thought made me a woman. :/

But I think all of this is heavily philosophical and subjective, so I’m not saying your feelings are wrong either. But to say that the only way for trans people to be is the way you perceive them to be is not just silly, it runs the risk of invalidating everyone else who doesn’t share your feelings on the matter. Our identities are our own to express, not yours.