It's a good thing git is a distributed system. In such cases, people can just switch to a different remote and push their branches there (with some care, of course).
Many of our projects are using SVN just because it's the easier one (at least until lately) to configure and set up locally. So that's a small win for SVN, and removes the issue of GitHub being down.
The real problem that we should be talking about is - Pull request based workflow many companies (including mine) have adopted. Which doesn't work when github goes offline.
I hear from lot of teams, they have switched to using github issues for project managment entirely, so as pull request and tickets can be "seamlessly" linked. That goes out of window as well.
But yes, you are right. Being able to copy it from my neighbor is nice.