AWS had a console login issue a while back due to the default region being us-east-1. There are a handful of other services that are exclusively available in that region as well.
I haven't worked with them in quite some time. (That's changing, so uh … looking forward to my next AWS outage?) This was more to show regional vs. global than any specific cloud provider. AWS is skating by here on account of not being sampled¹.
If I go waaaaay back (like mid 2010s), we did have an S3 outage. It was regional, even!
> GCP has AZ in the same physical complex.
I can't say if that's correct or not; GCP says,
> Zones should be considered a single failure domain within a region. To deploy fault-tolerant applications with high availability and help protect against unexpected failures, deploy your applications across multiple zones in a region.
That's an AZ, to me. (Or, alternatively & synonymously, a failure domain.)
¹IME over my career, though, AWS is fairly stable. GCP is too. AWS has its foibles, though. When last I worked with RDS (circa 2019), there were bugs.
AWS's definitions for AZ & Regions are by far the strongest in the industry.
GCP has AZ in the same physical complex. Azure Regions would be AZ's under AWS's definition.