I'm sure this helmet can defuse certain scenarios, but I'm doubtful it can reduce acceleration enough.
It's a simple equation: F=ma. I don't see players reducing mass anytime soon, so acceleration is the only candidate short of moving to non-tackle football or modifying DNA.
Also, I see how it may work in the heavily padded area of the helmet. It is less clear how this deformable helmet protects against side impacts. If it reduced concussions 15% but increases broken necks 3%, detached retinas by 15%, and broken jaws by 25%, is that a win? The best product isn't always the thing that solves a single problem brilliantly. It's sometimes the product that solves the most problems pretty well.
In case anyone missed the last line in the video that was in tiny, medium grey text on a black background:
A correlation between impact reduction and a reduction in concussion risk has not been established.