I think there are times when it's useful to be young and other times when it's useful to be older. Teenagers are always associated with rebellion but in fact teenagers are often some of the biggest conformists around (no offense to the teenagers here, just in general, lol). It's a very insecure time and they are desperate to fit it. Sure teenagers begin to defy their parents but that's pretty much a built in part of growing up and again, not that defiant in the grand scheme. As you get older, the idea is that your priorities start to change and you realize just how foolish your worries about popularity were and you become wiser that way.
But there are down sides to getting older too. I do think there comes a point where you naturally get set in your ways and it's very difficult to make significant changes in your beliefs and thinking. In that way younger people can come in handy.
When you get older, you tend to also become complacent. There are older people who still want to see things change and welcome the idea of things getting better... but then there's that portion that becomes selfish, nasty, and despises anything that makes them feel old (the younger generation, any swing in socio-political movements), causing them to be curmudgeons that want everyone younger than them to die in wars they wouldn't have fought in themselves.
There are 2 political movements in this country... one is furious about the fiscal inequality that leads them to pay more taxes than the corporations that refuse to hire them and buy up all the government influence to
keep them from paying taxes and not hiring anybody... the other is a bunch of people afraid of stuff that isn't happening, and angry that the government would, for a change, help its own people. People who are on every single government assistance there is who want to refuse any of that for the next generation (Social Security specifically).
One's not exclusively composed of, but mostly young people, the other is not exclusively composed of, but mostly old people. One's completely angry for the right reasons, the other's angry for completely selfish reasons that actually hurt them and help the very same major corporations that OWN the movement.
The thing is, the youngsters aren't completely disillusioned, bitter, and complacent yet. I'm sure they're going to get Stockholm syndrome and love the brain slugs eating their life sources in due time... but right now, the young have the illusion they can change things, while the old people can change things because they're literally TOLD what the big corporate interests want them to believe. And the worst part is, THAT movement started as wanting change from a party that's completely mired in Neo-con policies that BOTH the left and the right felt destroyed the country. We could have banded together to get REAL change, but everyone was so afraid a certain someone was going to take away gun rights as well as other Neo-Con funded rumors, that half of them crawled back to Neo-Cons who want the same things that ruined the country... huge corporate welfare and tax favors and more wars to assert the US's masculinity.
And I apologize for being political, but with age DOES come complacency. That's why we're hard programmed to be afraid of the next generation when the trouble makers make the biggest negative noise.