I used this analogy in another thread to try and explain what happens when an instance defederates from another: a trade route in the old sailing ship days. People are from different port cities, but each port has a ship that goes to all the other ports, so the people from the ship can trade/interact with the people where they dock.

So with that analogy, given recent events, the port city of Beehaw is one with more restrictive laws about behavior: if you aren’t generally respectful of others, they toss you out. There was a sudden influx at Beehaw of crowded ships from the ports of Lemmy.World and sh.itjust.works, both ports with less restrictive, more wild west attitudes. Beehaw found that their sheriffs were spending all their time tossing people who came from ships with one of those two flags, so they decided not to let those ships dock at their port anymore, or let their ships dock at those ports, for now.