Re: how many
"Azure has a functionality that AWS or GCS cannot match, same as the other way around."
No, it doesn't. It's not a functionality. It's an artificial licensing restriction which is an abuse of monopoly.
If you decide to use a proprietary AWS or GCP service that has no easy exit path to another provider, that's a decision you're making with your eyes wide open. Most sensible people don't box themselves into a corner when architecting cloud-native by using services for which there isn't an almost drop-in equivalent on other platforms.
If you've been running Windows servers on prem, from the era of dedicated physical tin, then moved to virtual machines, there's no technical reason at all why you can't move those servers to AWS, or GCP, or Azure, or Oracle Cloud, or any other cloud that provides IaaS services.
If Microsoft had a rule that said you can't move on prem licenses to the cloud full stop, that would be annoying, but fine.
It's the fact they treat Azure as a special case that is blatantly an illegal abuse of a monopoly in one sector being used to gain an illegal advantage in another sector.
It's not rocket science, and they deserve a massive fine, an immediate cease-and-desist, to pay compensation to customers that have overpaid to use Microsoft products on other cloud vendors, and to waive egress charges for anyone that was affected who subsequently decides to abandon Azure to migrate to another cloud vendor.