To really understand evolution, you have to look at it from the perspective of the gene, not the organism. The gene is immortal; the organism is just a temporary carrier of the gene.
If Asperger's is genetic, and it's still floating in the gene pool, it likely gives some benefit to the survival of the species as a whole. I just found out what I am a couple days ago, but from what I've gathered, and what I've learned about myself in 46 years....
Many of us have some fantastic skills to share with humanity. If all of us were completely dysfunctional, this set of brain wiring would be much more rare.
https://www.youtube.com/watch?v=At4Vmo13vJE
If I know how to make fantastic arrowheads, the rest of the tribe just might cut me some slack if I'm not good at socially stroking the tribal leaders.
_________________
Humans think they are more intelligent than dolphins because of cities, digital watches and nuclear weapons. Dolphins think they are more intelligent than humans for the very same reasons--Douglas Adams