It's not about 'who's at fault' really. It will sooner or later come up and it is better sooner than later for both parties. If I'm dating a woman and she doesn't mention that she already has children, which is a big deal for me, then we're both just wasting our times because that's something I can't compromise on.
I don't know why this even needs to be stated, but violence is not an option in either of these cases.
It needs to be stated that violence is not an option because many times violence has been used against trans women and the defense of the perpetrator was "I didn't know she was trans".
I guess nowadays people also informally call "having casual sex" dating. I'm also not sexually attracted to trans women if that's what you're getting at. We would not even be able to have sex.
Ok, we're on the same page regarding the violence.
On the other hand, I'd like to know what the OP, shtps, would think if they dated a transwoman without knowing she was trans and later found out about it. People have committed violent crimes because they didn't know, or at least claimed they didn't know as a defense.
So there is something there that needs clearing up. If you're attracted to someone and then later find something about them and decide you're not attracted to them after all, that's not the fault of the person you initially found atttractive. Agreed?