By all means, #movingtogitlab-dot-com does not solve the problem GitHub has (centralization), and moving to a privately hosted GitLab re-introduces the problem GitHub mostly solved (separation).
#GitPub is trying to solve this problem by defining a federation protocol for git services: https://github.com/git-federation/gitpub
To be clear, I do think that #movingtogitlab-dot-com is the right thing to do for now. Not because of Microsoft, but because GitLab – as a company – is as transparent as can be, and actually open source, which GitHub is not.