Dripstone Tortoise counts as a monster for taking up the monster spawn cap, but counts as an animal for not despawning when far away from players. I don't see any hostile mob spawns in the overworld without regular /kill @e[type=cave_enhancements:dripstone_tortoise] to clean up the excess entities.

Cave Enhancements version 2.1.10 for Minecraft 1.19.2, playing on Valhelsia 5, 5.0.14a