Probably because "Politics" is an english word and of the English-speaking users, Americans make up the largest portion.
I would expect Politique to be full of French politics and Politik to be about German politics and política to be about Spanish (or maybe Mexican) politics.
That is probably the most incorrect statement I've heard in a while. The internet is, to paraphrase Douglas Adams, big. You just won't believe how vastly, hugely, mind-bogglingly big it is. The english speaking part of the internet is a good chunk of that but it's certainly not "most" of it.
‘Politik’ is the same in the Nordic countries (Denmark, Sweden and Norway) as well, so that would have to be split up as well.
The same could be said about politics as Ireland, Great Britain, New Zealand, Australia and so on, have the same word for that.
If you create a community you should append the nation if it’s a common word. Otherwise it should default to worldwide.
You seem to have missed my point. The issues in any community, regardless of how many countries use the language associated with the community name, are going to favor the country with the majority of users. Unless you just register all the generic community names and squat on them, that's just how it's naturally going to wind up.