You see what you want to see
As do you
You see "arbitrary decision making" where I see mods looking at the rules, looking at the situation and applying best judgement.
You see "clashes between rival fangroups" which is healthy and fun, I see needless flamebaiting, disrespectful and offensive posting and little tolerance of a shared space.
You see "nothing in GM has changed in spite of the ridiculously excessive moderation that takes place", I see small but welcome changes and a reduction in the amount of posts that I come across that need to be dealt with and a drop in the number of reported posts in big events like slam finals or marquee matches.
Ultimately you and I are on opposite sides of an unbridgeable chasm on this one. I don't see much point in going around in circles making the same points. I'm happier with the way it is going, you're not. That's unlikely to change.