The contest you described (people with ADHD vs. autism) would have an enormously negative effect. But there are reasons to think it's unlikely. FWIW at least 25% of ADHD adults manifest autistic traits. Hardly surprising, clinicians regard overlapping neurodevelopmental disorders as the rule and not the exception.

An online community works when participants learn and share knowledge gained. Contests, with self or others, disrupt learning and sharing, hence by definition constitute "bad behavior". If it exists, the hyperwar you allude to will harm communities more than all LLMs combined could do.