I’m pretty sure this is a mob pathing bug, as evidence the frame rate inversely correlates with the number of mobs that want to reach somewhere but can’t. Eg farmed animals behind fences and zombies in water or when villagers bunch up at a door and can’t get in or out. If you jump inside the fence the frame rate goes up noticeably for example while the nether has almost no impediments to mob paths that don’t also break line if sight (by default anyway).
David Rolfe
I’m pretty sure this is a mob pathing bug, as evidence the frame rate inversely correlates with the number of mobs that want to reach somewhere but can’t. Eg farmed animals behind fences and zombies in water or when villagers bunch up at a door and can’t get in or out. If you jump inside the fence the frame rate goes up noticeably for example while the nether has almost no impediments to mob paths that don’t also break line if sight (by default anyway).