Mccartney and ringo have toured for years since the beatles including recently. They certainly could retire and don’t need the money - nor do the stones. These people do it because that’s what musicians do. They play.
Yes, journey, elton john - the list goes on. Yes has retained good sound until recently. The last time I saw them it was definitely quite a step down for them. But to be 60+ in age and still perform a Yes set must be daunting. So I cut them a lot of slack. Most jazz musicians play til they die.
McCartney and Ringo have. The Beatles have not.