I'll put this very simply. If I was mocking some girl about her small breasts, and she flipped me off, people would side with the girl. One doesn't even need to outright insult a girl with small breasts, just imply that they're a flaw. Also keep in mind how if a woman is insecure about her body, society empathizes with her and blames how everyone else is being unrealistic and cruel ("unrealistic beauty standards, body shaming," etc.)
When it comes to height, if a short man has a problem with mistreatment due to his stature, people will label him as "insecure." Either that, or he has a complex/syndrome. Doesn't take a genius to see how this is bullshit.