Performers/Artists Who Move with the Times versus Those Who Don't

That is a good point. I thought of him after I posted the OP. I can’t see the band as a whole making it through. But Johnny Rotten, or Lydon, or whatever he’s calling himself did make it work.

Will Smith comes to mind, although he’s putting out music these days (that I know of). Successful as a rap artist in the eighties, solo career later on, also successful as an actor–he’s matured well and still manages to stay popular, but in different ways than when he was first starting out. Sort of an anti-Britney, who’s still shaking what she’s got (a little more this time), just like she was doing eight years ago.

I don’t see this as being in opposition to what was said earlier. What Cash did on those albums wasn’t really much different than what he’d always done. That’s what made the covers so noteworthy. The covers got him exposure to a new audience… but he didn’t pander to get that audience.
(also Cash had been doing similar covers on a few of his 80s records as well. Rubin should get the credit for helping choose ones that worked so well)

The Red Hot Chili Peppers. They started out way back in the early 80s with a mix of punk rock and quasi-rapping vocals, later incorporated funk, then veered into gritty, soulful alt rock, and have been consistently developing their style for about 25 years, which is a pretty damn good run if you ask me. Their latest album, I think, was kind of mediocre, but it was still good. I think Kiedis and Co. can be counted on to be making great music well into their old age.