These are the de facto rules of living in society. You may criticise the rules themselves but you can't really criticise teaching the rules, you have to give kids the tools they need to navigate in a society, once they know what the default rules are they're free to expand and/or break them.

School is, for the vast majority of kids, a good framework for life.

It depends on how those rules are taught. If students are merely informed about or given examples of the rules and expectations, I would consider that to be more beneficial and neutral than my experience, which was to be harshly informed of these rules as if they were absolute necessities for existence, and punished excessively for alleged violations.

I was aiming for neutrality ;)

Back when public schooling started in the US, I gather that it was about preparation for factory work. And military service, I guess.

But I do agree with the dead comment that it tends to kill off creativity, curiosity and playfulness.

I don't know if it kills off those things, so much as make things unpleasant for people possessing them. You can very well end up with those traits intact at the other end of a high school education, you just won't like it. Then thankfully, the format and contents of a college course tends to be a little more amenable to those types.

I think it does, in the sense that people in the middle of the curve get used to not using them, which affects their work negatively.

Though it does suck to work in modern society without those qualities, or at least to be able to fake them.