I read it to say you still need the guard strips in a garage. In Florida we have a lot of extra framing in the wind code so there is usually enough cross bracing to provide horizontal paths without adding additional wood.
As for whether the various cables are allowed in unfinished spaces, that is the "physical damage" issue and it is in the eye of the AHJ. In Md it was normal to see RX stapled to running boards in garages, utility rooms and basements. In Florida they usually want something armored (maybe Smurf) and some places (like Miami) wanted conduit. I would ask the AHJ and see what the current feeling is.
I would not be shocked to find different inspectors in the same jurisdictions had different ideas of what was subject to physical damage and whether that damage was severe or not.
It is one of those areas that I wish was better defined in the NEC.
A posting from California, and he hasn't seen NM in a garage? How does the power get to the door opener or light?
I will admit that the practice seems to be to staple it to the stud, running it vertically to the rafters, then through the top plate and follow the perimiter around ....
i see NM cable and AC or MC cable all the time in open wall garages, i have been told over the years that the cable has to be protected with guard strips even though it is installed in the bay between the wall studs. and i can't find that anywhere in the code.