[yosame]

There's definitely a decent body of evidence to suggest ADHD is associated with emotional dysregulation, but I'd be surprised if that explanation turned out to correct.

ADHD isn't simply a lack of dopamine, but a dysfunction in dopamine (and noradrenaline) regulation. It can involve too much dopamine (like with hyperfocus), and not enough dopamine in different loci. This isn't even mentioning the non-dopamine/noradrenaline understandings of the pathophysiology that are still arising with further study.