“Popular usage” is all very well and good until you have to quantify it in some way. No way it wouldn’t be a complete mess.

For example: the body of water between the UK and France. The UK calls it “the English Channel”. The French call it “la Manche”. It has no official international name. In Google Maps both names are used depending on what country/language you are using. Choosing one via popular usage would not be a good solution.