I choose Github just because of its indisputable scale and financial success. Github pushed git to where it is now. Not linux (we don't even use git remotely like the kernel devs do), not Linus, or any previous system. Github did it.

Say what you will about their ethics, their structure, their politics, that company did this thing and they're now more important to the world of software products than any prior company in that role ever has been.