In order to understand this story, we'll need an appropriate mental model of Git. At their core, version control systems save previous states of a project. That way programmers can wind back time to figure out how bugs were introduced. An analogy could be recording a chess game so that interested observers could analyze important moves. Take, for instance, Deep Blue versus Kasparov, 1997, Game 6.
This is a companion discussion topic for the original entry at https://jlericson.com/2021/08/24/git_rewrite_1.html