Mobs, especially in Dripstone Caves, have a chance to struggle pathing around Pointed Dripstone stalagmites.

They attempt to approach the player, but upon coming into contact with Pointed Dripstone (within the cubic meter "block"), even a stalagmite only one "block" tall, they have a chance to stop moving, only turning to look at the player as the player moves around.

If the Pointed Dripstone is broken, the mob is knocked away, or the most direct path to the player becomes moving away from the Pointed Dripstone, the mob will resume moving. They have a chance to get stuck again if they come into contact with another Pointed Dripstone if more of it gets between the player and the mob.

Here is a OneDrive link of the bug occurring multiple items in an exaggerated situation.
bug.mp4