I am pretty ADD. For me, moving to a system using org-mode helped a lot. It didn't make me an "organized" person (hah!), but it has repeatedly kept me from losing track of important things and has given me a place to take tasks/reminders/notes/etc off my mind. Being able to write something down and trust that it will surface back when I need it has reduced my mental load and general anxiety.

I haven't been super organized or consistent in how I use org-mode—org-mode is great at letting me discover my own workflow and adapt the tool to what I need rather than adapting myself to the tool—and I've gone through periods where I lost the habit, but, overall, it's been a concrete improvement to my life. I've found that seeing it as a tool rather than a "system" made a big difference for me. I've never liked productivity systems (especially at work), but having a tool I can use in whatever ways helps me is a qualitatively different—and better!—thing.