Something like that. I've seen periods where it felt like there was relatively little moderation, and I have also seen moot and other mods banning people for very whimsical things, including for the mods own amusement. And, of course there is auto-banning to stamp out shit-posting/crapflooding/whatever you want to call it, overused memes, dubz, advertising, etc.
I haven't been on there in a while, but if moot says to keep ponies on /mlp/ then don't be surprised to see bans for posting ponies on /b/. It's not even a /b/ rule; it is a /mlp/ rule. It keeps the peace. If /b/ becomes unhappy (due to too many ponies), and /b/ doesn't have the numbers to retaliate against /mlp/ then /b/ might well go flood other boards to call attention to their discontent.
It's not a random rule at all though. Pony pictures were once 90% of what was posted to /b/. If the ban were lifted out would likely devolve into that place again.
