Doubtfire isn't pro-tranny, it's the opposite. The whole show is on the premise that men are men and women are women, therefor a man dressing up as a woman is fooling people and worthy of laughing at. Furthermore, that doing so is so extreme and unpleasant, one would only do so for something as important as their kids.
That movie literally came from the time when we were so pure, DIVORCE was still taboo and sad.