Im not sure why Ray Davies is included in your poll, but anyone who wrote that many great songs qualifies as a legend to me.
Little Richard---if he thinks he is a legend, then he has every right to. So much of his stuff still has a visceral punch that would put others to shame.
Ted Nugent was always a cocky, self-congratulating peacock who probably considered himself a legend when he was first starting out, so he doesn't count.
I don't enough about George Clinton personally to comment.
However, Michael Jackson has taken egomania and audicity to a new level. In his ever-evolving twisted mind, he is now lashing out at everybody and everything because his last offering did not sell 30 million copies. He solidly considers himself a legend, there's no doubt about that. I consider him a NUT of the first order.