I got mostly A's in K-6. Once in 4th grade another student pitched a tiny fit about how I always got A's on spelling quizzes.
After that my grades started to decline. I was having trouble with the increasing demands of the work. Graduated high school with a 2.25 GPA or something like that.
In college I was diagnosed with ADD.
The industrial-age education system wasn't a problem for me, until it became a problem for me.
But it really isn't the problem, because ADD can prevent people from being able to focus on things they want to do of their own free will in their own time. Industrial-age education isn't an issue there.
So, being unable to maintain focus especially on the boring bits, they end up sucking at whatever it is, which gets depressing.
As an example, I'll note that common characteristics of people with ADHD include hyperfocus [1] and higher creativity [2]. They are also more easily bored. Is this different? Yes. Is it bad? Certainly in the context of the standard educational experience. Do stimulants help? Sure, but they also help everybody cope with boring things. Almost every office in the world has a coffeepot. We have built a system that most people need stimulant drugs to function well. That some people need more or different ones than others to fit the system's needs is unsurprising. I'm just suspicious that the disease model fits it particularly well.
As an analogy, consider who can reach which cabinets. We just accept that there's a pretty wide normal variation in human height; some people can reach higher shelves than others. We also recognize that kids grow taller. If we started declaring kids below the median height had "Height Deficiency Disorder" and started giving them growth hormones because they couldn't reach the top shelves, that would be pretty sinister. Especially when that happened to the ones who were just younger in their grade, and therefore naturally shorter. Especially when it's possible to build cabinets differently, to provide assistive devices, and to help short kids learn how to deal.
So yes, we definitely don't want kids to fail. But I would like us to treat medication as a last resort, and to start being more accepting of neurodiversity.
[1] https://www.webmd.com/add-adhd/hyperfocus-flow
[2] https://www.psychologytoday.com/us/blog/here-there-and-every...
Also, it's an analogy, and not meant to be taken literally. It's just meant to give people a feel for what unnecessary medicalization might be like.
I also think you're ignoring the extent to which a neurological difference has been medicalized here. Depression is truly debilitating in any context. Here ADHD is sometimes being diagnosed due to a poor fit between an artificial environment and and children who would have been seen as "normal" had they been born a week later. Is there actually a problem with those kids? Or is the problem with an industrial-age education system that expects kids to demonstrate obedience all day and drugs the ones who don't? That's far from the only way to educate children; maybe the problem is not the child's brain, but that we expect all children to fit a very specific mold.