Really depends on your POV.

If you say "all rap is like what I hear on the radio", does that also mean that "all folk is what I hear on the radio"? So folk music is defined by Westlife and the Corrs? Hell, I hope not!

How much of what's on the radio from other genres is manufactured rubbish? Why should rap be any different?

Re the violence and sexism, blues has a long line of that, and folk music is replete with murder ballads and sexist, racist songs of every description. "Know thyself" indeed.

Incidentally, I've tried to see something good in Atomic Kitten, Will Young, Gareth Gates, Liberty X, HearSay...

Graham.