Who is it for? The average user here seems to be a grumpy mid 50’s Scotsman.
It’s here I would guess because
Not everyone fits that demographic
Anyone can read the forum without registering (I think?), which would include minors (as opposed to miners)
Because there’s a decent, nicely written magazine behind all this and the owners presumably don’t want it cheapened by mumsnet/Facebook group swearathons that detract from the content.
Have you read the content of some of the Facebook MTB groups? The unfiltered language, uninterrupted and casual throwing around of F’s and Jeff’s just makes most of the comments unreadable vile garbage. Not swearing forces you to write properly (well most people) and this place is imo much better for it.