I think socialization is a bit broader than 'spending time with peers'. School is a microcosm of society - full of institutional logic, dysfunction, and pervers

I think socialization is a bit broader than 'spending time with peers'. School is a microcosm of society - full of institutional logic, dysfunction, and perverse incentives. It's a perfect training-ground for teaching people how real organizations work. If you are socialized in well-functioning groups with shared interests and common purpose, you miss out on all the hairy stuff - and you can end up expecting a lot more from the institutions you encounter as an adult than they'll actually deliver.