I think it is more likely that people are emotional about the question and thus shut down to exploring it intellectually.
The intellectual exploration is understanding that we have a better understanding of medicine, and ADHD is just like other conditions we can now treat.
but sure, lets ignore over a century of research and progress because someone wants to ask "what if" and treat all that as an emotional response.
Meh, medical research in terms of psychology (disorders) is largely based on how well a person functions in modern society, which is sick. Since the OP asked the question in terms of sociology/evolution, it makes sense that the medical literature would not say much about it.
No, the question is based on an unevaluated premise.