> it comes off as super invalidating.

Once this is on the table, it's hard answer in a way that doesn't come across as being the asshole. But that's kind of my point. People tie identities and emotions to labels. It reframes how people react. Since it's real, you're given support. If it were fake, you'd get scolded. The shift in view that I got from Scott Alexander is that the arrow points the other way around. Since we see people who can benefit from some support, and we generally don't want to be assholes and want the support to be paid by insurance etc, we have to declare the thing as a Disease(TM). But this categorization is in good part necessary due to the bureaucratic system we live in. There are many ways that societies have conceptualized such things. All the way to demon possession. In comparison blindness is much easier to understand mechanistically.

No. Knowing that I have ADHD is something that would benefit me even if I spend the rest of my life on a remote island with no human contact. Yes it is as real as blindness.