If model names and numbering are so inaccurate, why get so worked up over a single inaccuracy? Had my car been made for JDM, it would be badged as such, a Fairlady280Z, yet still maintain the same engine, same chassis and same visuals. They are the exact same concept.
In regards to my 'wrong-headed' approach, how would you describe a 260Z? I would say it is an S30 chassis, equipped with L26 and chrome surrounded separated rear tail lights. Now using the term 260Z as a reference point, a 280Z is a 260Z with an L28, or if we take a step back, an S30 chassis with an L28 and chrome surrounded separated rear tail lights.
Sure there are multiple variations of S30s and S130s, but if we all must be so incredibly accurate when referencing our cars, there's no point to it at all. What's the difference between a '79 S130 and an '82 S130? A LOT. Yet they are both S130's, both Fairlady280Z's in Japan and both 280ZX's in Australia. Personally, I have a wedge shaped hunk of metal on 4 round things with 4 round light up things on the back. Somewhere on it, it says Datsun.