Before JAR-FCL came along it was noted that after qualification private pilots continued to fly actively for about 3 years after which time there was a marked reduction to the 10 year point when 90% were no longer active.
This was quoted as an example when the 5 year licence came in, to justify the costs by stating that as less than 90% would be flying after 10 years the cost of issue and one renewal was no more than the cost of a lifetime licence.
Apart from the reduction in numbers qualifying (arround 30%) in 15 years has anything really changed?