>There seems to have been some disconnect where we’ve just decided that young people have no longer got any rights.
Segregation happened. Much like racial divides, it's easier to see people you aren't exposed to on a daily basis as something less than human. That, and when people are expected to be less than human, they start acting like it (the lack of opportunity for personal development directly delays when it happens).
Children, of course, have it worse, because they don't know (and some never really figure it out) that they're getting screwed; the foundation of fighting for rights is knowing you should have them in the first place.
And while there may have been a good reason for this in the past (1910s industry was very far from being a pleasant place to work), safety regulations and the increased number of service/knowledge jobs relative to the more unpleasant ones (as well as safety regulations where applicable) as well as increased automation would make workplace apprenticeship programs much more viable. The political will (of the people who have rights) can't be changed unless they see those who they oppress like themselves, and showing that they can accomplish objectively useful things (not schoolwork) is a good way to do that.
Of course, the very task of creating programs that make children useful is significant, and we figure that school isn't that unpleasant for most, so [corporate humanity] will do nothing to change their status. We won't teach the children dissatisfied by the current system that there's something they can do about it either, because that would destabilize the system as it stands.
>Schools should be a place where children feel safe, not a place where they feel locked up.
The two are much more similar than you realize. The feeling of being locked up directly stems from the complete elimination of risk (i.e. the feeling of safety). And a school with no playground and no technical subjects where students are seen and not heard is a perfectly safe place, much like societies where the concept of risk is antithetical to the concept that individuals only exist to serve said society tend to have less violence but never actually prosper. Development requires risk.