I can save the government a lot of money: the rise in autism is not due to cases actually rising, but due to more diagnoses by a better-informed public and medical community.
I initiated my daughter's testing, not her pediatrician or her school because I recognized her mild symptoms. I can confidently say that she would never have been diagnosed on the autism spectrum if I had not been aware of autism symptoms and had her tested.
We weren't the least bit surprised when our pediatrician recommended testing for our son before he was even two. We'd just sensed something was different, even from his infancy. Even the specialists told us that he had some signs of autism, but not others. Although I understand the term has fallen out of favor, he was called ' very high functioning' by many of the specialists who worked with him. He's something of a poster child for early intervention. He just turned 20, and he's a sophomore studying engineering in the honors college at his university, having graduated second in his class from high school. He's been on the dean's list since his first semester. He's very friendly and outgoing, and most people would probably just characterize him as 'a bit nerdy' (or even a lot nerdy, depending on one's disposition).
A friend of ours we met through an autism support community has two sons of his own on the spectrum. They're similar to our son in many ways. The friend, in his early 50s now, says he only realized that
he's autistic because of his experience with his sons. When we were kids, children like that weren't diagnosed as autistic. They were typically regarded as just 'weird'. Looking back I knew several people growing up who were likely on the autism spectrum, but were never diagnosed because if anyone was even aware of autism, it was only exemplified by severe cases.
I also see a similarity with other conditions, like dyslexia. My dad is dyslexic, but was never diagnosed or treated. Having been born in a lower working class family in 1938, he was just dismissed as 'slow', which is a real tragedy, because my dad is anything but slow. Had he been born in 2015, by now some teacher would likely have said, "I have this student who's excellent at math and has no problems with verbal language, but is struggling with reading". He then would have been tested and diagnosed, and could have learned ways to help overcome his difficulties with reading. My dad is, as I said, a smart guy with a genuine curiosity about the world around him. If he could have satisfied his curiosity with a library card, I wonder how different his life would have been. Not that he hasn't had a good life, but it's definitely a good thing that fewer kids grow up without specialized help regarding such challenges, be they autism, dyslexia, ADHD etcetera.