1. Lawsuits are completely irrelevant to what is actually causative. E.g. there is essentially no evidence silicone breast implants are carcinogenic, but that didn't prevent implant manufacturers from going bankrupt due to legal judgments.
2. From your own link: "The studies in people are observational. Some conditions that might prompt acetaminophen use during pregnancy, such as fever and severe infection, are themselves associated with autism and ADHD in children." Observational studies may be a good point to start further investigation, but given how many observational studies have been thoroughly debunked from a causative point of view, they should be completely ignored as evidence IMO.
There’s a lot of interesting observational research on this topic, and in particular I found this paper[1] interesting because it shows a similar link with Tylenol and autism in young infants, but did not find the same effect for ibuprofen, which to me almost rules out fever/infection as the root cause.
There was another paper I saw that even suggested the anti-vaxxer conspiracies may stem from the fact that doctors and parents give Tylenol to their kids to manage the side effect of some vaccines.
Interestingly, there is also a separate body of research[2] that has shown experimentally that acetaminophen causes emotional blunting and reduced empathy in adults - could be related?