It is true that every cloud provider uses some edge/colo infra, but it is also not true that most (or even really any relevant) processing happens in those colo/edge locations.
And limiting to just outside the US, both aws and Google have more than ten wholly owned campuses each, and then on top of that, there is edge/colo space.
Google lists their dc locations publicly: https://www.google.com/about/datacenters/locations/
Aws doesn't list the campuses as publicly, but https://aws.amazon.com/about-aws/global-infrastructure/regio... shows the AZ vs edge deployments and any situation with multiple AZs is going to have buildings, not floors operated by Amazon.
And limiting to just outside the US, both aws and Google have more than ten wholly owned campuses each, and then on top of that, there is edge/colo space.