Yes, I think that's a good description, but with some caveats.
It's like how it is with people with global intellectual disability and learning in general: We learn socializing more slowly and with more difficulty, and need more help learning it. So that parallel makes sense.
However, unlike many of those with a global intellectual disability, we have very scattered skill profiles, with some skills much above others. So, instead of just lagging behind in socializing, we're also using the higher-level skills to compensate (for example, we might practice facial expressions in the mirror or read books on body language). And we may be held back by other skills that are even worse than our social skills; for example, someone whose sensory input is routinely scrambled, overwhelming, or hard to process would have to deal with that before they could learn to process social information more accurately.
Instead of my social skills being universally behind, they're behind and scattered, depending on whether I'm able to compensate with other skills.
My ability to recognize faces is worse than that of a six-month-old baby; I'm faceblind and memorize people by voice, hair, etc.
My ability to understand humor is about as good as that of an adult my age, both because I think in an associative way that lends itself to the double-meanings and twist endings of jokes, and because I got interested in it and studied it explicitly.
My theory of mind is atypical, but relatively good, about as good as that of a twelve-year-old. I have to think harder to figure out others' perceptions and I use logic to do it, and I have to remember to do it rather than having it come automatically. When I don't expect it, when I don't deliberately try to understand others, things fly over my head to a degree that seems to be even worse than the average autistic's comprehension.
My expressive language depends on my energy. If my energy is good, and/or I am writing, I have superior expressive language skills. But when I'm stressed, those skills start to become unusable.
I cannot easily maintain relationships. I take the initiative to keep in touch with people about as much as a toddler would--that is, if they are not there, I do not particularly miss them, even though I care about them.
I am more pro-social than most people, mostly because of my philosophical stance on the matter of human life. I do not feel very much distress when other people suffer; rather, I feel as though something is damaged and I want to repair it.
If I'm typical--and I suspect I am--then autistics probably have scattered profiles like this in socializing as well as in general. We are definitely delayed, since that's part of the definition of autistic, but it's not an even, across-the-board delay.