The author of the Search Engine pod just had a two-parter about his "ADHD":
https://podcasts.apple.com/us/podcast/whyd-i-take-speed-for-...
(The history of regulating Speed in the US is actually fascinating).
I could focus just fine all my life, then suddenly I couldn't. I've talked to other adults who are experiencing the same.
And it's funny how people get super torqued when you say something like this. There is a lot of room between "I have legit ADHD" and "I am addicted to my phone".
Sometimes I could not start a project at work for weeks - then I got off Twitter.