Maybe author knows that too, but wants to talk about it nonetheless. First line of article: “Commits are a terrible metric for output, but they're the most visible signal I have.”
What about number of working features or system completeness? Current state vs desired state is fairly visible.
Using AI we can make 1000s of commits per day. This metric becomes even more pointless in the days of AI. If we increase sales, New subscription count, reduced bug count, reduced incidents etc., those can be real metrics. I'm sure I am preaching to the choir.