Lots of people deny trans and non-binary people even exist. There are also those who want trans people to stop existing. That's why people go around reminding everybody. How have you not worked this out yet?

I have not seen trans people claiming to be better than cis people. What I have seen is cis people disparaging trans people. I've also seen both men and women disparage the opposite gender. I've even seen the constant (and somewhat sexist) reinforcement and policing of gender norms that happens within society such as girls are better at cleaning and men are better at repairing things and so on that's mostly perpetuated by cis people.

I say all of this as a typically presenting cis man in a male dominated field. Despite that I still have to contend with gender norms. For example I am not athletic, and do things like baking that make me stand out to other men who subscribe to traditional gender roles.

So who again doesn't treat people equally?

Edit: I think you are also confusing feminists and gender abolitionists with trans people. Trans people are not the ones normally arguing that gender doesn't matter, as it's understandably quite important to them specifically. Gender abolitionists want to get rid of gender norms and other things associated with a person's social gender. Feminists need no explanation but surfice to say that the majority of them are cis women.