I'm playing Skyblock v4.02 from here: https://www.planetminecraft.com/project/skyblock-4/ I have a basic nether fortress farm that just has one-block-wide spawning rooms where I can hit the mobs' feet. However, mob spawning is super slow in the nether, compared to the overworld. It takes several minutes to get ~15 mobs, and it never seems to go above that amount. My view distance is set to 16, and I don't think I have any rules issues as I am getting spawns, just super slowly.
Does anyone know why my nether mobs are spawning so slowly? Being a skyblock world, there is no other land in render distance so it's not an issue of mobs spawning elsewhere.