Monopolies exist exactly like this. With them not competing fairly and coordinating with one another so as to not encroach on the others territory.
Ever wonder why despite there being dozens of ISPs in the country, you’ve only ever got an option for like a main one, and an intentionally shitty one to make the main one look better?
It’s all a rigged game.
Those are the only 3 that matter at the top tier/enterprise class of infrastructure. Oracle could be considered as well for nuanced/specialized deployments that are (largely) Oracle DB heavy; but AWS is so far ahead of Azure and GCP from a tooling standpoint it’s not even worth considering the other two if AWS is on the table.
It’s so bad with other cloud providers that ones like Azure offers insane discounts on their MSSQL DB (basically “free”) licensing just to use them over AWS. Sometimes the cost savings are worth it, but you take a usability and infrastructure hit by using anything other than AWS.
I honestly, legitimately, wish there was some other cloud provider out there that could do what AWS can do, but they don’t exist. Anyone else is a pale imitation from a devops perspective. It sucks. There should be other real competitors, especially to the US based cloud companies as the US cannot be trusted anymore, but they just don’t exist without taking a huge hit in terms of tools, APIs, and reliability options, to AWS.
Multi cloud is very difficult to do well.
Multi region is already hard enough with transactional management not being easy to split between the regions, and multi-cloud is another order of magnitude more difficult than multi region.
With that said, use2 and others were still up, so if they were just multi region and failed over to east2 they would have been fine.