Saw the one episode lately where 3 men were lost and the crew on its sister ship did put on their PFD's (for all of about 1 hour! ) Seems just too bulky and slows them down too much.
Seems 2 factors ;if you go into the water, you only have a couple of minutes to live anyway. As said, by the time the boat turns around and tries to find you in heaving seas, you are a gonner anyway.
Also get a line from a 600lb pot around your leg and no matter what amount of flotation you have its not going to make any differance.
It surprised me that they havnt developed a fast deployable rescue system !.Its a multi million dollar industry and no-one seems to look out for the individual.Its as though they get paid well ($12,00 to $40,000 for a good 4 week season) and its the risk they take.
You would think some boffin would develope a system on the stern that deploys a string of bouys with maybe a small self inflated raft in the middle.Could be fired off the back at the first shout of man overboard.; something like the "squid' anti submarine charges in WWII.
Some sobering facts below;