Alan Turing was chemically castrated for being gay. Society finding you conventionally unattractive and thus passing you over for a promotion at work isn't exactly the same thing. People are discriminated against for lots of reasons, many subconscious, but protected categories didn't emerge from a vacuum. The reason being queer is protected whereas being short or ugly isn't has nothing to do with queer people having more power in government (lol) but because there was a history of actual violence, much of which was state-sanctioned, against queer people.

Then again being in a protected category has never really helped me avoid discrimination; having enough money to afford competent legal representation did. I wonder how many Americans can afford that when the majority can't make a $500 emergency expense. I'd argue the poor are the most clearly discriminated against group in our society and clearly there's a history of direct and indirect violence against them on that basis alone, but capitalism requires their existence and so they're invisible to our judicial system.