@Eve I personally hate people who say that. It's so often used as a dismissal of the real psychological pain that trans people are going through.
I have a gender, it's real, and I need to be in it now. If they think gender is so not meaningful, then it won't cost them anything to treat me as the correct one.
Even if it would be better if we were all free from gender roles, telling a drowning person to learn to swim is not helping.