I travelled over to the west coast and spent some time with the Artificial Intelligence team within Google at their headquarters just off Venice Beach in LA. Like all who visit that facility, I am constrained by an NDA in talking about what is going on. However in their bid to establish "Quantum Supremacy" the team, led by Hartmut Neven, talks not in terms of decades but in a timetable that is the technology equivalent of tomorrow. For the avoidance of doubt, the "tomorrow" that I refer to is the timeline for building and operating a universal quantum computer.I interpret "the technology equivalent of tomorrow" as being within two years. Check back here at that time.
No, Google is not going to succeed. This is not like self-driving cars, where it is clear that the technology is coming, as prototypes have proved feasibility. For that, computers just have to mimic what humans do, and have several advantages, such better sensors, faster reactions, and real-time access to maps.
Despite hundreds of millions of dollars in investment, there is still no convincing demonstration of quantum supremacy, or any proof that any method will scale.
Google is all about scale, so I am sure that its researchers have a story to tell their senior management. But it is covered by a non-disclosure agreement, so we do not know what it is.
You can bet that if Google ever achieves a universal quantum computer, or even just quantum supremacy, it will brag to everyone and attempt to collect a Nobel prize. If you do not hear anything in a couple of years, then they are not delivering on their promises.