The answer would really be that only the US Navy and US Coast Guard uses free deployment anymore...
Everyone else uses Winchmen. Simple, less risk of losing the swimmer.
The task is on par with some special forces types, and the requirements for fitness are very similar. I know several, and if you think there is a large difference just because one group jumps from 30 ft you are wrong I believe.
I have played "Victim" during one class' Final Exam in Nroway a few years ago (for 330 Sqn) and it was NO walk in the park.
Cheers
H.