An example should help put this whole thing in perspective.
I'm a regular visitor to the UK Climbing forum (
http://www.ukclimbing.com/forums/). This is one of the biggest and most popular UK forums on the internet.
Even without registering, you should still get a fair impression of the style of posts considered acceptable there. You don't have to know what they're talking about.
There are plenty of forum guidelines too (
http://www.ukclimbing.com/forums/info/guidelines.html)
But even so, most of the threads are not "family friendly" in the way geocaching.com likes it to be, due to the robust and opinionated style that many participants are used to.
Try this one, for instance (the first I picked at random);
http://www.ukclimbing.com/forums/t.php?t=315894
...along with rude words and off-topic posts.
There is a "chat room forum", where things get much more fruity, but that's off-limits unless you've spent two minutes registering.
The point is that this is a totally acceptable forum (to the UK climbing community, which is probably bigger than the world geocaching community), yet if GC.COM were moderating it would be closed down completely within hours...
I think that any attempt to make an internet forum totally "world wide family friendly" is bound to run onto the rocks fairly regularly, and that we're suffering from over-ambitious expectations in this area.
That's why my view is that the best place for UK-related geocaching discussions is on a completely UK site with UK moderators, with whom we can discuss appropriate guidelines to suit UK sensibilities and culture*. Remember that the Groundspeak "UK Forum" is simply a US Geocaching Forum section, dedicated to talk about UK caching. Not a dedicated UK forum.
(*Edit: "UK sensibilities and culture" is not really what I mean, as I'm aware that it's not just UK people that are able to deal with a little more "robust" debate, but I can't find a phrase that sums it up very well).