One can have a required language for some purposes, but it's impossible to think people would use it for everything. The premise is weak.
What’s the maximum number of first-class-official languages that are usable for all official use and actually equal in stature?
- Belgium has French and Flemish, though they’re essentially partitioned by region (i.e. in practice, you can’t rely on Flemish in Wallonia or French in Flanders). The language blocs have their own separate political parties and everything, and have the bare minimum amount to do with each other, like a divorced couple who can’t afford to move.
- The UK recognises Welsh and Scottish Gaelic, though they’re only used in their geographic areas (and even there, you get periodic cockups like some monolingual anglophone pasting a Google Translate error into the Welsh part of a sign).
- Ireland seems to be making a reasonable fist of having English and Irish; most business is conducted in English, though pretty much every Irish citizen learns Irish in school and spends a few months in the gaeltacht where English is not spoken, so I’d venture that the sorts of errors seen in Wales wouldn’t occur there.
- Sweden, meanwhile, has five official languages you can conduct any official business in; they include Sami, Yiddish and Romani, though not English, which almost everyone of working age speaks to a reasonable level. I imagine that dealing with the government in English would probably be easier than doing so in Romani, if those were your two choices.
- Not sure about Canada and Switzerland, but I get the impression that they’re geographically partitioned, if perhaps not as much as Belgium. In Canada, packaging seems to be bilingual by law, though Québec is aggressively francophone, with STOP signs reading ARRÉT and bans on English-language signage, whereas elsewhere, everyone speaks English. In Switzerland, meanwhile, there’s a sharp line between the French and German-speaking parts, which is sometimes called the “Rösti ditch”, and the Alps divide the German- and Italian-speaking parts. Meanwhile, more people primarily speak English than the fourth official language, Rhaeto-Romansch.
So from the above, I’m guessing that after about two languages at most, the country partitions into language regions which develop their own cultures, and ultimately economies and political orders.
I mean like wrong? At least speaking for switzerland, there's no 'sharp line' like there's literally bilingual cities and cantons like Biel/Bienne when I moved closer to the french part the local dialect had more french words in it it's not a 'sharp line' at all. The Röstigraben is more used as a political term similar to something like the urban rural divide because the french speaking cantons are reliably more left than the swiss-german speaking part. As for Rhätisch more people speak portugese than it but I don't know what point that is for what it's worth my partner loves watching the Rätisch program and has gotten quite good and understanding more and more so that nowadays she can get the gist of it.
Like shit I 'conducted business' in french this week my guess is that if I was on the opposite side of the röstigrabe they would be able to speak german with me, actually they did in Fribourg so....
The maximum number of first-class-official languages is how many people are willing to support them. Again compared to Belgium the political parties aren't separate if I lived in the french part even not being able to speak a single word I'd be able to do shopping since everything is in german, french and italian, any government document they have to give out in an official language. In school I learned french so again. All about like actual effort.
Edit: Actually talking about Rumantsch there's literally a somewhat big indie game in Rumantsch you should check it out it's neat.
Your dataset is a bit biased towards countries of the Global North.
South Africa for example has 12 official languages.
Senegal has French as official language, but very few actually understand it.
The EU is not a country, but it has a parliament with most languages being live-translated.
