@b0rkJulia Evans: I use this to manage forks, and so have some small insight. Imagine a piece of software like dwm, a window manager with a small initial featureset that is extended via patches. Any meaningful user maintains their own fork, even if that "fork" only adds a config.h to set configuration values, as this project has no config file.
So I use pushremote to pull and rebase my patch set onto upstream master/main and push to my personal master/main. Does that clarify why this would be useful more than what you already have?