Stating the obvious
Kat states the obvious here: that trans people aren't stupid and understand that they are trans. One of the arguments that detractors use is that trans people deny biology which could not be further from the truth. But then if you believe that sex and gender are exactly the same thing, you will just have a mental block over something that is really so simple to understand.
Kat lives her life with a lot of privilege and she knows it, but still is out there making supportive videos for the trans community.