Why did John Barry and David Arnold stop doing the Bond scores?

John Barry suffered a ruptured esophagus and was unable to do LTK. He also expressed that he was getting tired of doing Bond. When he was asked back during the Brosnan years he wanted too much money.

David Arnold was replaced when Sam Mendes wanted to bring in his own composer, Thomas Newman. And now Fukunaga wants to use his own guy.

It would be nice for David Arnold to return one day, he often tried to capture the spirit of Barry's pieces and produced some beautiful compositions.

I would like to think having been away for so long now, waiting in the wings, that he would have a classic score tucked away, saved for when he is asked back to Bond, but perhaps that's wishful thinking and he just uses his best for whatever project he's working on at the time, which is fair enough.

Barry held out to do the Bond song but the producers wanted a pop star as a marketing thing, and the sort that writes it themselves. All very well, but when they did that, the songs didn't really chart too high mostly. They weren't smashes. Barry also said he suggested they might want to go in a different direction for GE anyhow.

Barry did the great Bond-like All The Right Places with Lisa Stansfield for that money film with Demi Moore and Robert Redford, can't remember was it Indecent Proposal?
Barry had his bag of Oscars by then, he did what he wanted he didn't really need Bond.

Arnold got dropped for SF because the director always had Thomas Newman I think. Again, Arnold's services are oft required so he took the view he got to see a Bond film like everyone else for the first time in over a decade... as a fan.

I guess it is just the sound of the era, but David Arnold's Shaft score (released June 2000) is very reminiscent of the way he mixes the more modern techno sounds with the classical orchestra and Bond themes in TWINE (released 7 months prior).