if Scirra internationalize their support for another languages, the problem of always relying on someone to keep the board working will always exist.
And that's why since the website existed it's always and only been an English-only board and other language communities have always been left in the hands of the people speaking these other languages.
Some made external forums, some made Facebook groups. And people looking for those always end up finding it in the end. Even if it is after having come round those forums.
It would be nice indeed to have international boards on Scirra's forums for the users.
But from Scirra's perspective, it could quickly become a moderation nightmare that they don't want to (understandably)/don't have the resources to deal with.
You proposes yourself for a Brazilian board today, good.
But what happens when tomorrow you move on to another website/tool/whatever ?
Scirra is left with a brazilian board they have no way to moderate nor support, and probably would have to shut down anyway.
So, for the time being, better not make one in the first place, and let communities make their own websites/groups/whatever on the side and deal with support/moderation on their own.
If Scirra finds a good way to handle such international boards, I'm confident they will do, as they are aware of your suggestion/request (you're not the first to bring it up).
Nevertheless, in the current state of things, it's likely not going to happen.