[jackewiehose]

Yes, I remember using zsh and in my experience this was barely useful since most Makefiles are auto-generated with hundreds or thousands of targets.

> one could always have a 'help' target that prints a short documentation

Sure, that's fine. But the point is that if you have an unknown Makefile you can't (or shouldn't) just execute it without knowing what it will do. Makefiles should be treated as individual programs just like any other executable and there's no guaranteed standard way to get help from it.