r/science is usually pretty good at spotting the issues with studies like this, and 'lo the very top comment:https://www.reddit.com/r/science/comments/10mrbrl/comment/j653ida/?utm_source=reddit&utm_medium=web2x&context=3

When I was a kid in the early 80s the ONLY people called autistic were the incredibly small minority with Savant Syndrome ( https://en.wikipedia.org/wiki/Savant_syndrome ). This changed over time (to be clear: for the good) to the modern spectrum diagnosis. But I really don't think there's an easy way to control for this change in a study, and it always feels kind of reckless when researchers do. You throw something like this out there and people start panicking about vaccines or drinking water or whatever for no reason.