Autism is literally defined by a deficit in social skills + restricted repetitive behaviours and nothing else so that is basically what gets treated - the symptoms gets treated with behaviourism and the underlying causes of that behaviour are ignored. GI problems are comorbid in like ~40% of autism cases. Do schools stress getting these autistic kids exercising and teaching them how to cook healthy meals so they can overcome these struggles, live a life without pain, so they can not only live a higher quality of life but have an easier and more pleasant time being social? Sometimes - but the overwhelming emphasis is simply making them act more normal in a very simplistic and direct and to the point way. The system isn't designed to improve autistic kids quality of life you see, it's designed to make them less troublesome for the people around them, and hold them accountable for the trouble they're causing, that's people's mindset.
There is a very cold and unemphathetic attitude towards autistic kids where they're just expected to be iron willed stoics who behave using a fake personality that pleases others around them while their underlying issues basically get no attention from the system. I think if autistic people were treated with more empathy, as less of a monolith, as being defined as being more than "social deficits + repetitive behaviours", we would go a long way.