ctrl-S is deeper, older code. And yes, a bug in that would affect both manual and automatic saving. Meaning the bug has greater exposure and therefore would be detected faster.
More easily detectable bugs are less of a problem, because lack of alarm indicates lack of those bugs.
It’s this: (P => Q) => (!Q => !P)
Basically P is the bug existing and Q is someone detecting it. The more powerful the implication arrow on the left side of that equation, the more powerful the implication arrow on the right side. Or if you prefer probabilities: a greater conditional probability on the left means a greater conditional probability on the right.
Worse bugs that affect more systems are less worthy of the user’s attention.