Earlier quoted context omitted.
The question isn't really how many would think it meant nanonmeters, it's how many would recognise it as nautical miles.
In aviation? Literally everyone. Context clues should make it obvious.
And how many would assume that the incorrect unit abbreviation would mean something else? If I said Kbps and KBps, it's an entirely different unit of measure. NM and nm are VASTLY different, and unless you are already familiar with measurements in Aviation and know it's Nautical Miles, your first instinct is gonna be to read it as the unit it's supposed to be.
The article title is talking about location data and computers, I've seen many people forget floating point precision when comparing and getting bit by tiny differences at the 10^-9 or smaller. That seems just as obvious on the outset as non-unique location designations in what the average person would assume to be a dataset that's intentionally unique and unambiguous.