What they actually mean is the opposite. They want to make Azure the easy choice when developing with Docker. They go on to say it can take hours or days to get the integration set up manually.
If Azure “just works” and the other clouds take days to get integrated, owning Docker would let them make Azure integration a priority while neglecting or sabotaging integration to other clouds. The gap gets bigger and Azure feels even more like the obvious choice if you want to get anything done.
IMO one of the major cloud vendors will buy Docker this year. Microsoft seems like the obvious choice right now.
Which is a playbook they've demonstrated as recently as last October, on Mover[1]. It used to allow you to migrate data between a whole host of sources and destinations, and the guides/help docs even still reference those capabilities. Microsoft acquired it and made it free, but have turned it into a one-way tool: the only supported destinations are now Azure, Sharepoint, and OneDrive.
The question is: did they do this to win market share? I think it makes _total_ sense for MS to make a bunch of GitHub services free. I also think it's harmful to competition.
One of the worst policy choices the US has made in the last 30 years is judging antitrust almost _entirely_ through the lens of "monetary cost to end users".
The less reasons there are for using GitLab (private repos was one thing which got me initially, using GitLab over my self administered servers to move code around and share with friends) the better for keeping their quasi-monopoly.
Again, honest question, obviously IANAL.