To shut down GCP, they would be shutting down the same services and infrastructure that power their own services. The dogfooding memo from years back is being taken to heart, and you're seeing more and more exposure of internal services and infrastructure.
The scary thing would be if it ends up reducing the rate of innovation because they worry about changing APIs or services too much; obsolete accumulates quickly when you're serving large numbers of people because most business want to write once run till it's dead. But this is true of any service that exposes anything but an extreme abstraction.
