Yeah I suspect that people are being over-diagnosed, but I also suspect we're catching dramatically more cases than we were previously. An overcorrection if you will.
Sure. We're also changing rubrics and even inventing new conditions, and we don't really try to graduate them. On top of that, there are perverse incentives. Amphetamine is an amazing drug, and since some people get it, those who don't find it hard to compete. So, we have to give them a way to get it, because the side effect of not doing that is popping them with felony drug trafficking charges at the airport. I don't blame anyone for playing the game.
Suspecting is reasonable. So is suspecting it is under-diagnosed.
Ranting about how all these diagnoses are fake is not.
Time may revise our opinions of the current state, but with the exception of malpracticing professionals, the diagnoses are valid for given state of medical health knowledge.
The "left handedness" graph change that occurred once we stopped punishing people for being left handed. Same sort of thing here. We'll stabilize once we get good at diagnosing it and stop stigmatizing it. We're in a period where the graph is changing, and that change is disruptive, but it'll level out.