Your defensiveness aside - it's actually not a "trope" or a kneejerk reaction to notice that the rates of ADHD and ADHD medication have doubled in the past couple decades in the US and are significantly higher in the US than in Western Europe. The US has a pattern of over prescribing medications - the current opiod epidemic is an example. My understanding of this is that it's most likely there is over-diagnosing, and therefore overmedicating, of ADHD, and that's bad.
"Are there bad parents who don't want to deal with their kids' behavior" - there are, sure, but that's not what I think is most common. My intuition is that bad parents would just not care what their kids are doing and leave it to the school to handle. If I had to guess, I would guess that the modal problem parent is one who, understandably, wants what is best for their kids and is concerned about what the schools are telling them. The schools, for their part, want kids who don't overly disturb the system. The doctors hear about a problem that they have the pharmaceuticals to treat.
I don't think the people involved are evil and acting out of malice or laziness but I do think that this group works together to create a system where a fundamentally boring place (school) has a problem managing people who are fundamentally bad at being bored (boys) and they, in part, solve that problem by giving them drugs (ADHD medication). I've been thinking about my choice of the word "complacent" from earlier, and maybe it's not quite right - I originally meant it in the sense that the natural state of the boys is to think of school as a problem and rebel against it and their medicated state is to not rebel against school as much or to the same extent.