Age in itself is not a factor in a pilot's ability to do aerobatic manoeuvers in a fast jet - being medically and physically fit enough and practiced in coping with the rigors of the manoeuvers is.
All the pilots in the US "Starfighters" Team - flying a much higher performance aircraft than the Hunter - must be in their 60s/70s from their bios:
KVDV, Inc. - Starfighters Crew
https://www.youtube.com/watch?v=jJ6K_U1zPi0
https://www.youtube.com/watch?v=gOwIdAXlgPg