I'm not usually someone to complain about a comment or opinion, but this conflicts so much with my experience that I feel compelled to respond. I was diagnosed about 1.5 years ago, in my 30's.

I would argue that yes, "that's an ADHD symptom". One symptom does not make a diagnosis, but if you recognize yourself definitely do your research and consult a professional. Especially for the many people you know who show similar behaviour.

It took me a long time to convince myself I might have ADHD, and during and even after the diagnosis I still had my doubts. Looking back, it was incredibly obvious if you recognize the symptoms. I'm still amazed I got this far in life without professional help, no doubt largely due to my supportive environment.

I would _strongly_ argue that it is not accepted that ADHD is overdiagnosed.
I've done a quick read through of the studies you linked, imho none of them actually support the claim of overdiagnosis.

[1] "Overdiagnosis is defined here as occurring when a person is clinically diagnosed with a condition, but the net effect of the diagnosis is unfavorable. Misdiagnosis (when a child is incorrectly labeled with an ADHD diagnosis instead of an alternative condition) and false-positive diagnosis (when a subsequent clinical encounter reveals a wrong initial diagnosis) are not the focus of this article."

Unfavorable here is:

- medication can have side effects

- it might be used as an excuse to stop trying/caring

- there's a social stigma

[2] This metastudy is about mental disorders in general, mostly referencing studies before 2000. The only study supporting the overdiagnosed claim is a german 2012 study;
https://pubmed.ncbi.nlm.nih.gov/22201328/. They sent case vignettes to 1000 psychologists, psychiatrists, and social workers. For the case vignettes which matched several (but not all) ADHD criteria (DSM-IV), 16,7% gave a diagnosis, and 2x more often for boys vs girls.

This proves that the therapists did not strictly followed the criteria, but does that mean that they were wrong? This is no simple blood test. They're asking someone to give a diagnosis based on a 3rd party report of a patient.

I remember in my case there was a computerized quiz with easy answers and long artificial delays, to test if you can stay focused on boring tasks and measure your response time. If you give me this test on my pc, I will very quickly switch to another window or take out my phone. But in an external environment as part of an expensive test I specifially asked and waited a long time for? Sure, I'll be polite and keep staring at the screen.
The screen was an old tft by the way, with a crappy unshielded vga cable picking up interference, causing ghosting issues in the different colour channels. If I lifted the cable hanging under the desk with my leg, I could almost make it go away.

Anyway, all of this was reduced to a number (my average response time), and ultimately to a boolean (can stay focussed). It's not an exact science.

Also, maybe the criteria are wrong? Or at least incomplete? Prior to DSM-V, ADHD and ASD were mutually exclusive. That seems absurd now, but the 5th edition only came out less than 9 years ago (may 2013), so after the above study.
The DSM is "only" a consensus of a group of professionals. Over time our understanding of things change, and that consensus might change. And over a longer time, some of those professionals (and maybe a few new ones) come together and try and update the DSM.

[3] This article raises the question, but does not actually claim ADHD is overdiagnosed. Sure, some people might seek stimulants, and might successfully fake their way to a diagnosis. But that's a problem not exclusive to ADHD. Diagnosing ADHD is not straightforward, and should be done by experienced professionals.

I suspect there is a large pushback in the USA on stimulant use as a result of the opioid crisis. But for the people who actually need the medication the process of actually getting it is already difficult enough, and should be made easier, not harder.

I'm open to having my mind changed, but so far I have not seen any evidence that ADHD is overdiagnosed, let alone that overdiagnosing is increasing.