[soldehierro]

In the case of Spanish, I can't speak for French, having an academy (the RAE in this case) regulating the language sounds like a problem on paper, but really isn't a problem in practice. The RAE accepts Americanisms and treats American Spanish just as it would European Spanish (referring to the continent(s), not the country) and encourages lingusitic diversity. Anglicisms are only discouraged when an acceptable Spanish alternative is in WIDE use (but never prohibited, as can be evidenced by the sheer quantity of anglicisms in the Spanish language.)

Spanish is very willing to accept new words, and as diverse as English in terms of decentralization. Grammar doesn't make or break a lingua franca, number of speakers does, which is where English really shines.

So what does the RAE do you ask? They write grammars and compile dictionaries, describe phonology and answer people's questions on Twitter. Just like what Merriam Webster or Oxford would do, but the RAE has official backing and creates consensus among the hispanophone countries. English is a regulated language, just not officially regulated.

[kube-system]

I'd say it's more accurate to describe Webster and Oxford as documenting established usage, rather than being informal regulators. They generally view their role as being purely observers and not as active influencers of the language.

Some other language authorities do not take a usage-evidence-based approach to defining their dictionaries, and take into account cultural or historical concerns.

[yongjik]

Oh how I envy you. Here in Korea we are stuck with the tax-funded imbeciles of National Institute of Korean Language, whose hobby is saying "ALL you Koreans are using the Korean language wrong!" with a straight face at every occasion.

[vidarh]

Similarly in Norway the authority in charge often proposes Norwegian alternatives to Anglicisms, but they'll yield if an import becomes dominant, and will even reverse official reforms if they fail to gain traction.

[orwin]

I which french academy was this tolerant.

[Bayart]

The problem of the French Academy isn't that it's intolerant, there are linguistic bodies in Europe that are far more conservative, it's that it's too slow and simply cannot keep up.