sdc1989:

Consider this: Joseph Joestar is the only Stardust Crusader who’s still alive and well right before the ending of part 6.

Joseph Joestar, a man who was falsely proclaimed dead once and actually died only to be revived, also outlives: his best friend, his parents, his grandparents, his “granduncle” (Speedwagon), his grandson, and his great-granddaughter.

Also consider: for the few moments when he was dead during part 3, Joseph might’ve met with his family members and the other Crusaders one last time, since the afterlife is canon in the Jojo universe.