[throw0101a]

> As with all customary units, it favors a specific use-case at the cost of errors and conversions, has limited accuracy and doesn't handle orders of magnitude.

The nautical mile was not 'customary', but based on mathematical properties. Specifically, it was defined as one arc-minute (1/60 of degree) of latitude. Degrees of latitude are measure from the centre of the Earth and not the surface.

This is no more arbitrary than how the metre was defined:

> The metre was originally defined as 1⁄10,000,000 of the meridian arc from the North pole to the equator passing through Dunkirk.

* https://en.wikipedia.org/wiki/Nautical_mile

It is now been translated in relation to the metric system as 1852m.