> ... my understanding is that in Europe it's virtually unheard of to have an adult diagnosis.

Can't speak for the whole of the continent but UK here and I got my ADHD diagnosis a few years shy of 50 years old. Wasn't tricky at all, just a long-ish (8 month) wait for a non-private diagnosis (not full NHS but via an outsourced provider via Right-To-Choose).

When going through the DSM-5 questions (during an ~80 minute interview) I was asked to give examples from both current life experience and from childhood, and that was enough.

Honestly it's really gratifying to hear that people around the world are getting the help they deserve, thanks for sharing.