Hum, I'm not an expert on Google cloud, but for AWS, regions are completely independent and run their own networking infrastructure. So if you really wanted to tolerate a region infrastructure failure, you could design your app to fail over to another region. There shouldn't be any single point of failure between the regions, at least as far as I know.
Although I guess depending on how your own infrastructure is setup, even a multi cloud provider setup won't save you from a network outage like the current Google cloud one.