Trans people exist. They always have, and we have records of hundreds and hundreds of thousands of them - even in societies that have imposed harsh legal and social punishments.

First, you ignored the substance of what I said and focused on the cheeky summary of the previous poster's position.

Gender is, and always has been, a cultural construct. Sex is the biological reality on which gender is based. Some cultures have a third gender, recognizing the dysphoria you mention (as well as the biological reality of intersex people). None of this changes the fact that POLITICALLY penis people with gender dysphoria are inserting themselves into the social, cultural, and political spaces of biological and culturally self identified women, and demanding the right to those spaces. Trans women experience horrific discrimination, but they don't experience that discrimination as women. The discrimination against women is different, and needs to be acknowledged as such.

I know women who have been verbally abused by trans women at a women's conference for not centering trans issues in the feminist agenda of the conference.

Yes, there is gender dysphoria because gender is a social and cultural construct. Recognizing this doesn't change the fact that that dysphoria is rooted in a biological reality that is the basis for our gender constructs. That biological reality is also the basis for millennia of subjugation and oppression of women. One might argue that gender emerges as the cultural form of sexism.