The costs would be trivial for the vast majority of Software Engineering companies. Talking about corner cases is useless as they often need a custom specialized solution anyways and wouldn't be using GitHub in the first place.
And for most companies, building and managing an SCM is absolutely not their core competency. Your point is valid, but not in the way you're trying to convey it.
Nope, sorry. Github offers cloud and on premise offerings. If you choose cloud and your company can't handle a 45 minute service outage, that's just a bad purchasing decision. You do realize they make most of their revenue from on premise enterprise customers and that none of those customers were impacted? The solution was there the entire time but they can't force people to use it.
