Autism wasn’t recognized as a distinct condition until like the mid 1940’s and Asperger’s Syndrome wasn’t recognized as a separate condition until the mid 1990’s… so perhaps our understanding of autism as it has increased, our ability to recognize it in people has also increased leading to more diagnoses. Not because there are more cases now, just because it’s being recognized. When need to measure an actual increase and find a causal relationship.
Two things can be true at the same time. There is a greater proportion of cases being recognized now, AND there is also an increase in the number of cases. Thats not just my opinion, thats the scientific consensus. As I said before, most of that seems to be due to the increasing age of motherhood, not Tylenol.
We need a comparable number from the past to see that cases are actually increasing the whole point is that our understanding previously was limited compared to now so you can’t compare aggregate numbers because of confounding variables, being the limitation on our ability to recognize it. And again, you need to establish an actual causal relationship between correlating variables to actually find an answer. We haven’t.
You said “there is also an increase in the number of cases” that is not supported by the scientific consensus and the research you provided doesn’t say that either. It gives a possible relationship between maternal age and risk of autism. It says nothing about autism rates increasing.