Earlier quoted context omitted.
Are there any good iconic systems you know that identify languages directly?
I don't think such a system does or can exist. e.g. nl-NL is distinct from nl-BE which is distinct from fr-BE. Using a country flag doesn't work if a country uses multiple languages. Languages themselves don't have icons to go with them like countries do, but even if they did it wouldn't distinguish between the same language spoken in different countries, which can matter a lot for how things get localized. nl-NL use…
(and yes, language switching menus you can't understand are dumb, especially for more complicated cases where names don't even look similar, but unfortunately common)