Yet those same people are our older generation now. The apple didn't fall too far, even if they wanted it to. I'm in my early 20's and most people my age (like every other generation) think they'll be revolutionary. I'm generalizing here, but people get older, put the bong down, and try to get office jobs (which isn't all bad).
It happens at the same at every point in everyone's life. Everyone thinks they can change the world, but after a while, you realize the world is going to be how it is, and the best you can do to "change the world" starts with the smallest acts of kindness