Can you explain or perhaps just comment that neither the USCG or USAF have adopted the USN approach? What do they know that USN does not?
I think Griz is right...the AF just doesn't think in those terms.
For the USCG...I don't have an answer, but I do wonder about a couple of things. First, I wonder if the CG has a significantly lower experience of their aviators going in the water, percentage wise. Thinking about what they fly, it's multi-engine fixed-wing and multi-engine helos. They of course have had their share of mishaps, but does that compare to the sheer number of jets the Navy has put in the water off the boat? Again, I don't know the answer, but I'm guessing the Navy has thought about that, which leads to...
The second thing is more about risk mitigation. Yes, the CG has reflective material on their blue helmets, which works in certain conditions. But if you're the Navy, why
wouldn't you make your helmets both reflective AND contrast the water?
These are guesses, and maybe it's all poop. But from the Navy's standpoint, there doesn't seem to be a downside of having white helmets versus non-white ones other than coolness points (which I'm not opposed to, for the record).