Darn, France is really late once again, english we can learn in high school and even before, but imo it's more around 10-12 years old, and generaly the level of the english teachers isn't fantastic (well it wasn't while I was at school, apparently it improved in the past 15 years ^^)
A token in the sense of translating C2 my father work in public school, and at the beginning of the year, he was looking for some computer activity to have with the kids.
I introduced him to C2, he liked it but the fact that it was english only made it difficult/impossible for him to use with young children.
I understand the "it's not important" part of the reaction, I shared it too to some point.
But in the frame of using C2 in educationnal system for example, it makes it far easier and more believable to use it actively and efficiently if it is regionalized.
As mentionned earlier by Ashley, tutorials and some other parts of the site are planned to be translated too, making informations easier to get.
The point was raised that the forum were in english, so no need to translate C2, that's half true.
There are quite some regional forums/communities listed in the not so visible regional communities page.
From there it is up to people talking both languages to be active on both forums/communities to help out and spread the use of C2.
Ultimately tutorials and manual will be available in multiple languages, but still those forums should be the go to communities in your own language.