Counterpoint to this website: it is convenient to have symbols to represent things. I don't see them suggesting anything better than flags.
Only if the symbols make sense and there's a one-to-one relationship. This is a good move by Apple. Also, as a color blind person it is quite frustrating when people make content and use a flag emoji instead of a country name. Often mousing over doesn't work. Emojis are not semantic information.
A flag paired with a name, which the UI used to show, is as close to that as you can get. You can’t get exactly that because languages are not mathematical objects, they are organic, amorphous, ever-changing living things.