Well it's more that these sorts of library _can_ live on its own and not be coupled to a core business. Not to mention that in the article they talk about how other open source libraries had some pitfalls.
its perfectly reasonable to ask for it, and perfectly reasonable for them to say no :) i also wished they offered up the code, instead of dropping two measly bullet points. but they dont owe us anything
They're connected to open source, but i don't think the GitHub app is open source. Maybe it's not reasonable to expect