It was the push back against a school system that wrote children off too young and often because of their background not their ability. Children began to be taught to push for their dreams because they would never achieve a dream they didn't push for.
Along the way, the message that it didn't matter how hard they pushed for their dreams the majority of them would not achieve them and a good percentage of those that did would find that after a while, a job is just something you have to go in and do every day even if you're a brain surgeon, has got lost.
"You can be whatever you want" has gone far too far, but it's still something I'm hearing repeated everywhere. It's a lie and not surprisingly many young people are mentally fucked by finding out they've been lied to about something so fundamental to their lives.