It does seem that 'legacy' acts struggle to get people interested in their new music. A few manage it. David Bowie was always evolving and I love some of his later stuff. If it's just variations on what they did 30+ years ago then you will go with that you are familiar with.
I have started on the Bon Jovi documentary. They did have to work for success and it's interesting to see how they hung out with Springsteen. I hope they did okay financially as so many bands got ripped off or lost their money.
I may give the new album a listen.