When a company like Google announces something, you can bet that they are actually 10 years ahead of whatever they announce. Their system is most likely much more strong then they admit this article. However, there is such a thing as quantum resistant Bitcoin technology. it is a work-in-progress, but when it is complete, we will have protection against quantum attacks.
Well, more like the other way around, they are probably way behind to be considered "National Security Issue". But they will get an inspection, and if its any worth, be ordered to shut up from now on. And that silent moment, is what you should fear.
Any American company can be ordered to shut up. They call those gag orders. It cannot be appealed, and defiance means prison, even warning the public. Next best they can do is close the company without telling why, which is precisely what happened to a now forgotten encrypted email provider.
Google and most certainly IBM won't close over this. IBM is already used to this game, and Google probably is by now. I bet they were just wanting to get the contract from the government first.