(Sorry to put it harshly, but it's felt like we're all getting a bit spoiled. Especially compared to the old days.)
For better or worse, you are the product if you use a centralized, free service. And the only thing keeping those dominant players dominant is the blind loyalty we seem to give freely.
It's all about that convenience! I get that. But morals have their place, and in the coming months the world will show whether they care at all about centralization.
It's probably important to stay nervous about centralization. If we let our guards down, we could find ourselves on the short end of an upsetting stick. History has shown time and again that when companies have no incentive to compete, they tend not to try. The reason Facebook can be so free with your data is that there is no way to compete with them. With github, at least there's a way.
Honestly, the biggest thing holding back Github competitors is that they won't just make their service look identical to Github. Gitlab looks strange every time I run across a repo. Instead everyone wants to be different, and usually it's not better.