People who self diagnose themselves but never seek professional diagnosis

I still don't know what to think about this quite large cohort of people who seem to have means to get diagnosed, but never even attempt to do that?

From my experience they are also the loudest about their ADHD, but when I want to chat about strategies and techniques they use to cope with it, it's all a bit surface level "meme" knowledge and boasting about creativity.Just my perhaps very limited anecdotal data.

I dont want to be overly critical though as maybe there are some other than financial reasons not to get diagnosed that I can't think of?