But... you are using another online service to host the service yourself, no? And presumably they are also throwing in backups and redundancy of some sort... certainly it would take you a minute to set those things up, test them, monitor they are working... And isn't GitHub basically like everyone's resume these days?
I don't know... at some point you sort of just have to trust someone... be it the hosting provider, or the service provider. And I'm old... but I've had to untangle issues with CVS / VSS / SVN / etc... over the years I don't want anything to do with that crap -- if I can punt it to someone else to manage I'm OK paying some tiny subscription fee.
I think there's been one day in the last ~10 years when I couldn't use GitHub. To me that seems worth the $20 a month, or whatever they charge now.