I don't condone people not wearing life jackets but often they take them off because of the summer's heat. They just don't think anything bad can happen when they are having such a great time.
Some people think they are strong swimmers and can make it to shore but underestimate currents and water temperature. Strong swimmers perish too because they get thrown from the boat and hit their head and are knocked out. 
Blaming the victim does nothing but upsets the family and friends. I am sure there are many regrets and lessons learned the hard way without adding true, but hurtful words,  needlessly.