The New Yorker interview said his mother was a dermatologist, so I would tentatively assume his background is upper-middle-class. That's obviously an advantage, but then, most children of such families don't become rich and famous either.
https://en.wikipedia.org/wiki/Sam_Altman does list his high school, which is very expensive.
We do have this quote from the Esquire interview in 2014, which is rather telling:
For my eighth birthday, my parents got me a Mac LC2. And, you know, it was like… It was, like, $2,200 in 1993 dollars. It was, like, this horrifically expensive thing, that was not that good. 40 MB hard drive. And then we put it in my bedroom, and I remember about it, it was this dividing line in my life: before I had a computer and after.