When I was in eighth grade, my history teacher mentioned an interesting piece of trivia one day during class. "There's this disorder called Asperger's and people who have it have no social skills." I don't remember why he said this, but since I had recently been told that I had "Asperger's," it was a little more than interesting to me.
I was going to say that saying someone has no social skills is akin to calling them a corpse, but actually I guess some people open up to corpses in a way they don't open up to anyone else. So maybe corpses know something we don't.
I am socially impaired because I'm Autistic, but I'm also socially impaired because I'm gay. Some people are uncomfortable when they learn that someone is gay, so I risk an awkward silence if I mention certain parts of my life. This means I can seem quite withdrawn in certain environments.
If an American teenager's parents are from another country, don't speak English well, and aren't involved in American culture, that person is socially impaired if they go to school with kids who all have American parents.
We can talk about blindness and say that in a country where everyone was blind, being blind wouldn't matter at all. We can say that being blind matters less when blind people are accommodated by people who aren't. We can say the same thing about dyslexia. But while difficulty is constructed, impairment is not--a blind or dyslexic person lacks an ability that other people have.
But what does a person lack if they have no social skills? How can anyone be bad with people? There is more than one person in the world.