No. Absolutely not.
I didn’t know anything about ADHD, and I didn’t know he had ADHD. By the time I figured it out and learned how the situation could be improved, it was too late. We both suffered.
I’m not the kind of person who regards a failed relationship as a learning experience; I see it as just a waste of time.
I will admit that learning about ADHD has made me somewhat more tolerant of people in general. If someone is unreliable or whatever, I no longer think of them as bad. Maybe they have a problem.
If I had known about ADHD and how to help him and how to conduct myself within the relationship, then definitely yes. He was such a wonderful person!