As for triumvirates, all the 3 astronaut are still living about the Apollo 8 astronauts, who were "The Person of the Year" by the Time in 1968:
(1928 - ) Frank Borman
(1928 - ) Jim Lovell
(1933 - ) William Anders
Some ideas for 2021:
Gerd Müller; Diego Maradona; Bobby Charlton; Tony Brooks; Frank Williams; Agnes Keleti; Marsha Hunt; Sidney Poitier; Anne Buydens; Edmond H Fisher or Jack Steinberger or John B. Goodenough; Pope Benedict XVI;