I think this forum is mainly for English communication.
So if you don't speak good English, you should communicate in the local section. Otherwise, the bounty manager may hard to understanding what you say.
But we all know that only few campaigns are accepting post from local boards meaning the signature campaign participants must spread their post in purely English section
Requiring English proficiency is not the answer for spamming the forum because we are all came from different part of the world with or without good English proficiency..the only thing here is the manager must have translators so they will be the one to communicate fro those not good in english