Why piston aircraft remained useful after 1945

Did the Fleet Air Arm and Royal Air Force retain piston aircraft after the Second World War for missions such as counter-insurgency?

Both services retained some piston aircraft for a considerable time because they remained useful for varied tasks, though not necessarily for counter-insurgency.

The Fleet Air Arm and Royal Air Force kept some piston aircraft in use well after the war. They remained useful for varied tasks and could have long service lives. Counter-insurgency was not necessarily the reason for retaining them.