They do not, according to the dashboard, this issue merely affected connectivity between GCP and other cloud providers.

There was a different outage yesterday, which has nothing to do with the one discussed in this thread.

Given how much trans-continental/trans-oceanic network cable the major cloud providers own, they almost certainly have special trans-cloud network traffic infrastructure. Especially since so much of "The Cloud" is within a few 10s of square miles in a field in Virginia. I can easily see how one provider could majorly disrupt another provider by accidentally breaking inbound traffic on one of those links.

The bigger issue is that there's a lot of customers where they have split cloud deployments, which means the customers hurt even if they are stable within the clouds themselves.

If you are deployed in such a way that both GCP and AWS need to be up you're doing it backwards. Multi-cloud strategy is supposed to result in the intersection of cloud failures, not the union of them.

I have heard that many companies are multi cloud as a result of acquisitions, resulting in a dependency on both clouds.

"But all of our problems are fixed by going to the cloud!"

Yeah, I see that now. Makes total sense.