They can be learned to some me extent, but they are harder for some people to learn than others, especially those far off to one side of the spectrum. Actually, it is really easy to tell naturals apart from those who have to consciously study social skills, the latter being much more stilted and systematic than the former. I admit I find it really off putting when interacting with someone with heavily trained social skills (and I’m definitely not a natural). I prefer people to be themselves rather than pretending to be something else.