my grandfather started playing at 50ish and was 4-5 handicap by 65. He was really really good only hit 200-250 but very straight, and his chip/pw/sw were above avg.
when I was 35? or so, I was hitting drives over 300 yards in air. lol At least 3/10. Never could play under 80 ish regularly though, even in my HS/college days it was generally 8-12 handicap