> The day-to-day impact of being diagnosed is practically non-existant for me.

Yeah, as the old adage goes: with an ADH?D diagnosis you get to try drugs like lisdex or methylphenidate (or the non-stim options if those aren't suitable), but with an Autism/ASD diagnosis you get some pamphlets, coffee morning invites and a reading list.

I don't have a formal diagnosis but my child does and that made me read lots on the subject. Authors like Eliza Fricker, Ellie Middleton, Pete Wharmby amongst others.

It's opened my eyes to many other related aspects, specifically Rejection Sensitivity Dysphoria (RSD) and Pathalogical Demand Avoidance (PDA) and how those play into both ADH?D and ASD. In reading about them I've worked out just how much they apply to my-undiagnosed-self and how understanding the triggers and recognising the early behaviour has allowed me to adapt to minimise their impact.