Yes, it can, but my point was that it used to only mean multiple people and we don’t have any trouble using it to refer to just one

It’s the country codes for Germany, Austria, and Switzerland (Deutschland for the D, Confederation Helvetica for the CH). Those are the three countries with a majority of their people speaking German other than Liechtenstein, which is extremely small

Singular they goes back at least as far as Shakespeare. Also, “you” was originally a plural pronoun.