I'll bet anyone a dozen of Krispy Kremes this is bogus.
I'm not so sure. Israeli scientists are among the most brilliant in the world. If anybody could develop a technology like this, it would make sense for it to be out of Israel.
So... if I lose, I win?
You would win big. Seawater is in approximate equilibrium with atmospheric air. A liter water has about 21 milligrams dissolved air. Reduce pressure to half an atmosphere, get half it out, recompress to the depth pressure so the diver can breath it. Bring along a ten kw nuclear reactor to provide the necessary energy to process many hundreds of gallons of sea water per minute.