Daniel-
I also imagine that different Wikipedia language versions will come up with whatever policies best fit them.
That would mean giving up on the idea that there is a neutral point of view, and instead succumbing to local cultural biases. In the case of the English Wikipedia in particular, this would be highly regrettable, as it is used as a source in many different cultures with strongly varying values, but the majority of editors (and hence voters in such decision processes) are probably American and British. The other argument against this practice is that it might reinforce and spread values which are harmful. It is not our mission to establish standards of normality in either direction.
Don't get me wrong, I'm not saying offensiveness should not be taken into account at all. The "default view" of Wikipedia could hide certain images which are considered offensive by the vast majority of editors. But our real goal should be to make the decision what is displayed an individual one, rather than a community choice that is imposed on the reader. We could also, on the request of schools and libraries, associate certain IP addresses with certain filter settings. Ideally, this would just be a switch in stylesheets and not affect the caching of the article pages.
Regards,
Erik