Yes, but he is supposed to be the abstract idea of the dark side of Johnny. However, I agree, it is the one character in the show that can be ageless
I'm perfectly fine with Billie playing St. Jimmy. He just has to cut Oz out of the tour cycle to fit it in.
Just an FYI, Melissa Etheridge, she's no Billie, but not bad
https://www.youtube.com/watch?v=UNA1gwHsMpo