I don't know then numbers and haven't watched much of Young play but sacks are a bad way of measuring a pass rusher's true value. Pressures is better. Win rate, double team rate, etc.
Clowney was always a power player. Never had the explosion, bend, hands of an elite edge rusher. He's a tweener who can't stay healthy.
Also, a negative of rushing against right tackles is the QB can see you. Probably negates the benefit of rushing versus lesser tackles imo.