PFDs work, so do helmets and seat belts, but they are NOT a panacea for
accidents. **** happens.

Exactly! If NTSB wants a law that works, require that PFDs are kept accessible
and in good condition. That's enough.
I am the first one to say that when you are in imminent danger you should put
on your PFD but it is stupid to tell me I need to wear one when I an putting
around the back bay at the state mandated "slow speed" in 4 feet of water (or
less). In most of the Estero Bay you can walk ashore if the boat sunk.