I heartily disagree. The current approach is a constant source of disagreement and worsening of linguistic tensions. I am always running into minor tiffs over British vs American spelling that could be eliminated with multi-dialect support. This would also mean that when I run into a Britishism on an article that might be confusing or misleading to an American reader, instead of changing it to an Americanism and drawing the ire of the original author (or changing it to something neutral and probably drawing the ire of the original author), the original author's Britishism can stay, the Americanism will be viewable to Americans, and everyone is a little bit happier.
Getting to consensus, even if the process is acrimonious, is part of what we do here. If there is a localized expression, then it should be filed away, even if the original editor isn't happy with it. Getting to NPOV doesn't just mean overt biases, but also the less overt ones, one of which is geographic origin. So if you run into it, comment it or put it on the discussion page and keep going.