This particular story tells us little about these schools – it describes the perspective of a student, a client. This is valuable and I'm grateful to read it. However, I caution other readers against making assumptions about these institutions based on any given story.
I would know – I attended four of these schools. Some incredibly strict (even dehumanizing) and others a joy (one had season passes to the local ski resort). Most of them blended these two polarities. Students exhibited huge variation in responses, to the point that a listener hearing them describe their shared experiences would be certain they were discussing different places.
For example, some students thought it was abusive to require skiing and mountain biking two days per week (I disagree). Other students thought it was totally fine to be required to wear hospital scrubs as a means of stigmatization (I also disagree). Almost no one questioned social isolation as punishment – perhaps the most incredible abuse I routinely witnessed and was subjected to, considering the developmental phase of adolescents. My point: it will take a mosaic of perspectives to really understand what's going on.
I also caution readers against abhorrence towards parents. Consider those not-rare parents who have tried everything to help a kid who is on the cusp of life in prison, undergoing their 8th overdose, or being repeatedly raped and subjected to prostitution/exploitation. Consider that many of these schools offer a greater education than what's locally available. Consider that some of these schools are effective and relatively safe.
A final note that I believe clouds this topic -> We live in a puritanical, punitive society. Even for non-religious people, we have been inculcated with ideals of purity and expectations of punishment. These delusions and biases cloud this topic.
My final guidance is to read these stories with an open mind. This author was truthful, and we should listen. The next story you hear will probably contradict it but also be truthful, and we should listen.