Postcrossing language is English, and it’s told in the guidelines, which is good.
Also here in forum, in the “common” area the language is English.
Both these I find good.
But I suggest, when there is “use English”, there could be additional sentence for example “but remember, even when members use English, it’s often not their native language, and they come from different culture, so show understanding” or something like that.
I came to think this suggestion when some members thought my English is better than theirs, and they are afraid/unwilling of writing here, because with my “better than theirs” English I have few times been “accused” of rudeness and publicly analysed and determined how I am as a person, because of the way I write. Or not even what I write but the tone I use.
This type of expectances, that one should know and remember to use all politeness words and correct nuances used in some part of the world, scares away possible forum members. I know we still are allowed to be representants of our own countries and cultures, even when using English, but does the use of English cause English native speakers actually assume we would not only use “their” language, but we also try adopt their cultural habits? Maybe this is what causes them think people are rude?
I think this is like international airport. You don’t go pointing someone rude just because they act different than in your country, but most likely you think they don’t know something, or it’s their habit.
So: the “use English” is good, but I suggest something in addition there, so it would be maybe more welcoming to those who are not so good in English, and a reminder also to those, who are, that we are not trying to be in their country or imitate any manners. So even when we use “their” language, we are not on their ground. If someone is more skillfull, they can meet the other one halfway.
Problems here is, old members don’t necessarily read it anymore.
Maybe a pop up, like when a topic reminds some other topic? Or a reminder?