Before “unschooling” there was “deschooling”

So before “unschooling” became trendy and highly marketable, there was a push for school reform, Ivan Illich (a friend of Holt) published his book “Deschooling Society”.

https://infed.org/mobi/ivan-illich-deschooling-conviviality-and-lifelong-learning/

I get the need to address educational reform, but why was education harsh and punitive?