It's impossible NOT to copy someone's style as basically every music style developed from someone else's style. There's no beginning and there's no end.
Yet, there are those that develop a unique style of playing and make it their own. Still, they've been influenced by other styles. I think it's their arrangements, use of instruments, that creates THEIR sound.
Composing must be one of the hardest jobs on the planet. Ringo Starr said that he had given up on writing songs because each time as he'd written one John and Paul would burst out laughing since he'd once again rewritten a standard. I'm sure that we all have some Ringo in us.
So copying is good thing especially if it leads to developing your own style.
Now, what did Rap people listen to?
Speeches by Hitler, Goebbels and Mussolini?