What is it with older people and their hate towards teens?

That's to be expected. The older generation always has something to say about the younger generations.

Dont worry they'll feel the same way when they're older, its the cycle of life

It's their new fangled juke boxes and fancy rumble seats.

So teens don't hate teens? It's just older people hating them?

I fucking hate teenagers too. Dumbasses (myself included)

This seems to be a very inappropriate question to me.

Resentment or regret maybe. Jealousy.

They mess up my lawn.

ignore them.

I hate agism

They see the same people making the same dumbass mistakes they did at that age, I think.