So MS owns the default place where code is hosted, and the default tool people use to edit code. Neat.
Apple would try to switch everything towards their walked garden, no questions asked. Google would shut stuff down every two years. Oracle... I'm not even going to bother.
Amazon and Facebook could be interesting. Facebook is a bit shady, see the Oculus Facebook account debacle, but they're decent as stewards of dev tools. Amazon is also quite reliable for dev tools.
Would anyone really big be a better steward? Did I miss someone?
Facebook/meta seems horrifying. Some of their tools are indeed great, but I can just imagine having to use a facebook login to push code to GitHub or to download VSCode plugins.
Amazon is problematic for similar reasons as MS: since they are one of the biggest application hosts out there, bad incentives exist in terms of potentially allowing biases in their tooling to preference their own platform.