What's weird about this is that it sort of requires a baseline understanding of what sex, genitals, and sex hormones actually are to work.They believe that the definition of gender and sex can be defined by what people feel about and that's enough.
You have to know what male and female originally meant, then reject it and declare that a man can be a woman if he dresses like one, but also he can be a woman even if he doesn't dress like one, because clothes and stereotypes about femininity don't equal gender, but sex hormones don't equal gender either.
How the hell is this explained to the next generation of kids in sex ed who have no base knowledge of it because their parents were already indoctrinated? "Gender is just like this thing, you know? It's based on how you feel. And there are male and female penises and male and female vaginas."
We make fun of Tumblr users for saying their glitter gender or that their pronouns are universe/univerself, but if they were raised like this it's no surprising they think that way. Gender is literally meaningless, anyone can have any set of genitals and call themselves anything. So why not make up knew ones? Why not change gender multiple times a day? It's just a mood, and there are way more than two moods.