That GitLab uses/used Azure is public knowledge. They've blogged and spoken about it extensively - and that they are given a large amount of resources for free as part of their use too.
Not only that, they conducted a full infrastructure review and potential migration plan in full public view - again discussing widely their use of Azure and why the switch to bare metal wasn't going to work.
There have been multiple discussions about this here on HackerNews.
I surprised that anyone wouldn't know that Gitlab was on Azure.
It's still good to spread the word I guess - though to suggest it's somehow newly discovered information is a little disingenuous.
Regardless, self hosting, or a federated solution, should be a better exit route.
More so for developers with smaller projects, or with few collaborators or none. There was never really a good reason to lock oneself into Github to begin with.
There was one good reason - that's where other people were. Open source is fundamentally very much a social phenomenon, even if often in a specific, nerdy way of being social.