It is only a matter of time before someone here suggests you use self hosted gitlab/github enterprise. Ain't got time for that.
Though if your internal IT team had a VCS outage, it wouldn't be Hacker News news. Really it is just the scope of the outages (and commiseration) that has changed.
b) Outages are inevitable and if you're using a SaaS you get to blame someone else for it (and sometimes it gets resolved quicker)
However I do wonder sometimes, even with the resources and domain knowledge, if the super crazy scale these SaaS companies have to deal with tips the scales to be about the same reliability as a solid internal ops or IT team (who only have to worry about YOUR scale).