Also, welcome to America where a large segment of the population dismisses ADHD entirely, and presumes that everyone has the same ability to focus on uninteresting tasks, or presumes that those who suffer from ADHD and have hyperfocuses are lying because "you can focus on this, why not that?"
There is a middle ground, a concept that is so utterly lacking in the modern world.
ADHD is real. Unfortunately, there's no direct physiological test for it, it has to be observed via behavioral analysis, thus it's possible to get wrong. It's also not properly accepted as the disability that it can be without support and treatment. If a person has it, and is not properly treated at a young age, then that person is likely to have low chances in being able to get treatment as an adult. At that point, it basically relies on the individual being able to find a doctor who doesn't dismiss their concerns (because people are human and make mistakes, or have incorrect understandings).
ADHD medications are also very highly regulated, far more than opioids and other far more dangerous-when-abused medications. If an ADHD person is prevented from obtaining their medication due to factors out of their control, they risk major setbacks in all areas of their life that can be extremely hard to bounce back from without some type of external support.
Increased numbers of ADHD diagnoses does not necessarily indicate over-diagnosis. Of course the numbers of diagnoses will increase, how could there ever be a diagnosis before ADHD was identified and labeled? In the early 20th century, it was called "brain-injured child syndrome" and later "minimal brain damage". Those words also would have an associated meaning in the public eye, and people have historically not been good at dealing with things like "brain damage" and "abnormal people", so things like that tend to come with the baggage of stigma, further reducing chances of success and happiness in life.
I was diagnosed with ADD in the late 80s, when I was 7 or 8. Just on a personal, observational level, I can tell that I definitely have focus control issues in the classical ADHD way - things that don't interest my mind are nearly impossible to focus on, but things that tickle my mind's itch are extremely easy to focus on. There's also not control over which group any given thing falls into. I'm extremely sensitive to physical stimulation, unless something else overrides that on a physical level (like the aforementioned hyperfocus). Stimulants slow me down, rather than speeding me up (this is probably a good test for likelihood of ADHD). For certain things, my brain figures things out extremely fast (one of these days I might try to go on Wheel of Fortune lol). This is just "the way life is" for me, always has been since I can remember.
I would honestly like to see more research into how psychedelics interplay with ADHD. A few years back, I had a particularly deep experience with DMT that revolutionized how I think about time and human perception. It also fundamentally changed my focus control abilities for at least a good three months. At the risk of introducing a bit of "woo", it almost felt like the universe fed me a massive data-dump, that even to this day comes out in the form of my gut feeling. I've also had improved peripheral vision since this experience. I've also had similar, shorter lasting effects from LSD and mushrooms. I think there is a woefully untapped resource in psychedelics, that would be very useful for ADHD individuals. I think even a mindful, rigid microdosing regimen would be extremely helpful, with less of the side effects that stimulant-based drugs have. I believe this to be due to stimulant-like properties of the classical psychedelics.