Right, but I'm saying once they actually hit commercially useful breakthroughs (e.g. AI game changer/black swan) they certainly won't be sharing them any longer.

Or put another way, they could currently be holding back 90% of their current research and only releasing 10%.

I'm not saying that is the case, it's just I think private research into some fields is much more opaque than folks (myself) realize. Relying on Google (or any other private company) to publish findings is likely not a path for long-term success.