I think the difference is that back in the 60s it was a grass-roots thing where talented youngsters could get together, create a new sound and win followers of their own age. Then they got a manager. Nowadays the managers often create the bands from cute-looking kids and dictate the often synthetic, formulaic music, substituting gimmicks for creativity, and quirkiness and cuteness for originality. It's all a game plan to manipulate the youngsters and it makes them millions, but I don't think it does much for music. There are still creative young people out there, but I wonder if it's harder to get a breakthrough with the Cowells of this world controlling the market.
The earlier music came from young people's experience, thoughts and feelings, so maybe it did touch young people in a way that the latest pop music pap doesn't. But there is still good stuff out there that will stick in minds and hearts for a long time - it's just having a tougher time getting through.