Jimmy Buffett led one hell of a life and crossed paths with—and welcomed—all walks of life into his orbit. And so it was that in 2014, on Saint Barts, he took a liking to then Saturday Night Live Weekend Update host to be Colin Jost. “I was randomly seated next to him at a dinner, and I had never met him before, and I didn’t know it was him,” Jost recently told one Mr. Taylor Swift—err, footballer Travis Kelce—during the filming of the latter’s fledgling podcast, “ New Heights .” “I sort of noticed little, subtle hints that it might be Jimmy Buffett. Like, he would say something like, ‘Whenever I open a new Margaritaville…’” For what it’s worth, you have to give Jost the benefit of the doubt as, in his later years, Mr. Buffett had a sort of old-rich-white-dude mien that somewhat belied and even besmirched his storied, almost mythically rapscallion past and present wisdom.…