Its not due to added boyancy, as a professional diver i can tell you that wont help you here since many of these women are still dominating the non-weighted categories.. meaning boyancy would work **against** them since they need to swim down before they swim back up.
If it worked how you suggest then all the winners would be super fat dudes who just tie a bunch of weights on themselves, hold their breath, sink to the bottom of the ocean, then untie it and pop up to the top like cork, lol.
I've directly responded to every one of your comments. if you want to storm off just cause someone doesnt agree with you, go for it.. buh bye.
Tldr: men are stronger on average because their bodies don't have to worry about producing offspring. A woman and no man weighing the same weight is not a good measurement system for equal footing, and no amount of technique is going to let you be better than someone who has 10% more muscle mass and a measureably faster reaction time.