> Languages [...] are democracies

I think the French would like to have a word!

https://en.wikipedia.org/wiki/Académie_Française

(On the other hand, rules aren't binding, so it's more like a "will of the people (if the people's will is large enough)"?)

According to my one semester intro course, this is referred to in linguistics as either a "prescriptive" or "descriptive" approach to language. As I think you alluded to, while the prescriptive approach defines people's attitudes regarding how certain approaches to the language are viewed ("this is right/wrong"), it rarely ends up actually changing how the language(s) themselves get used and develop.

I took a French class last year, and the teacher spent a lot of time identifying differences between academy French and how people actually talk. Things like "Je ne sais pas" => "Chais pas," which sounded like "shay pa." It seemed like the people still had a lot to say about how French should unofficially be written and spoken, even if it couldn't be used in formal settings.

Well, thus is, strictly speaking, the difference between "I don't know' and "I dunno". Speakers know this is a colloquial saying.

There might be a few areas where official bodies are lagging behind usage ("postuler à" being one I have in mind), but I'd say that grammar nazis and teachers alike are actually somewhat effective IMO.

> but I'd say that grammar nazis and teachers alike are actually somewhat effective IMO.

We have no evidence this is true. Certainly historically we know it isn't the case, there very strong evidence surrounding how languages drift over time that exist alongside contemporary pendants later proving to have not made a difference. But we also haven't really had a society with near universal literacy before so maybe that changes the dynamic.

> "postuler à"

Today I learned that I used it "wrong" all my life.

I know, right? Languagetool brought it to my attention the other day. "postuler" == "to candidate" seems absent from the dictionary, though it's in common use.

http://www.academie-francaise.fr/postuler-postuler-pour

That's neat the teacher brought up the 'tiers' of formality. As an american kid in France growing up, the 'vous-voyez' was instilled early on along with evaluations over the years in written and oral style. You probably remember 'liaisons'? It's as though in the same way a vowel at the beginning of a word causes the last consonant of the previous word to be pronounced, as familiarity increases and formality decreases, the words themselves begin to blend. Somewhere between your examples there'd be "j'ne sais pas" and then if your a high school kid in 2005, "Saich aps"

The French verlan is a prime demonstration that, in point of fact, King Canute cannot stop the tide from turning.