It's not about providing service unconditionally - it's about have Reasonable (IMO) terms which don't give them license to turn you off whenever they want. I think it would be perfectly reasonable to specify they will do that if you were abusing resources, doing something illegal, being malicious, etc. - there needs to be some limits on when they get to shut me down. I can't consider it in any way reliable otherwise.
And, how would you phrase that in a legal document like a terms of service?
Who determines "abuse of resources"? Who determines "being malicious".
If the sole determination of whether somebody is crossing the line for termination lies in Github, then the legal result is exactly what currently exists in the terms of service.
If Github does not have the sole discretion to make the determination of abuse, then who does? A third party mediator?
