You usually find that people who say it's bollocks, have very little experience of trans people, whether kids or not.
I think gender was a strait-jacket for many people, e.g., toxic masculinity. But we've seen waves of resistance to repression, starting with women in the 19th century, then gays, now trans and gender non-conforming. Of course, you are bound to get bigotry in all these areas, women should stay in the home, we don't want gays around here, and how can a man be a woman. But I think it's unstoppable, people don't want to be strait-jacketed. And a lot of the scorn is fear, isn't it?