I was that kid (though I'd hit my head against walls, not punch myself), and 20 years later I can tell you that autism does have its advantages.

The suffering wasn't caused by my autism, but by society forcing me to behave in a way that was unnatural to me.

Now that I'm living on my own, able to shape my environment according to my needs, I'm not suffering anymore. I'm genuinely happy, and I've got a successful career in software engineering. And every day I experience situations where my autism helps me understand logical issues much more deeply, care for order much more (refactoring is <3), and allows me to speak out when needed.

you and I might have made it out the other side, but what about the ones who didn't?

Very few people are incapable of communication. Mutism is neither exclusively nor inherently autistic, and there are many other communication options available beyond voice (though they'd have to be made available to the child – that includes tools, where necessary, and training). Real-time spoken language is a complicated skill, and we shouldn't require that people master it before their needs are respected.

Punching yourself in the face is a sign of unmet needs. Sadly, the usual response to something like that is to (1) restrain the person, then (2) not try to figure out those needs, much less address them. I don't make a habit of blaming caregivers, but if an autistic kid's punching themself in the face enough for it to count as a character trait, there have been significant failures at multiple levels.

I'll repeat that. Punching yourself in the face is not an autistic trait. It's a caged lion trait. Put an allistic kid in the right (wrong) situation, and they'll do the same.

I'm not sure what your point is. What are its advantages? I wasn't aware of any.

It seems to me that GP was using sarcasm to express agreement with your comment.

Ah yes I misread.