This happens more often then you think. I’ve seen basically every minority group imaginable get told to develop thick skin and get over their “imaginary problems” (black, asian, indian, gay, lesbian, bisexual, transgender, asexual, straight, poor, rich etc), even on more liberal corners of the internet.
I don't think you're wrong to point this out, but it's also obvious that nobody is discriminating against men for being short or women for being fat the way people discriminate and have discriminated against people for being members of those groups.
I don't recall any red-lining against short men, separate water fountains or schools for short men, short-men not being allowed to get married, etc. Also, remind me the next time the NYPD sets up some extremely questionable surveillance of short-men at northeastern universities or a presidential candidate adopts banning foreign short-men from the country as part of his campaign platform.