Earlier quoted context omitted.
I said github, not git. You don't need to use a cloud service to use git for synchronization.
You don't, but are people really manually running "git pull" between their various devices, or are they using a (self) hosted git service? Even in the self hosted case, I wouldn't want the security of all my passwords to be dependent on my $5/month VPS not being compromised.
Also, what is there to compromise on a machine that basically runs just sshd with password authentication disabled?