I'm curious what you would change about (Western?) society to make ADHD manageable like it apparently already is in "many countries," in concrete well defined terms. Not sure how society could negate the emotional regulation issues that frequently come with ADHD. I would also emphasize there's a distinction between "a society where people with ADHD can function" and "a society perfectly suited for people with ADHD."
I'm sensing that ADHD is a label thrust upon you, and if you feel you function fine without any sort of treatment it's probably not accurate. It's also now occurring to me how hilariously easy it would be to troll any sort of mental health issue. Depression isn't a disorder it's just SADNESS coming from MODERN SOCIETY and we just need to uncheck the CAUSE DEPRESSION box in society's configuration.
Buddy if you are waiting for a Sign, this is it. It'll never get more concrete than this message I'm typing for you right now. Having a lot of doubts is common. It wasn't truly real for me until I started medication.
My broad advice is to find a good psychiatrist (and don't be afraid to switch if you aren't happy) and dig as deep as possible for evidence both for and against. Go in with confidence that you have ADHD symptoms, but keep an open mind since there are alternative explanations. A diagnosis of "no you don't have ADHD it's actually ____" is also important information to know, and you will regret letting it drag out if you do have ADHD.