This is more of an improvement rather than a bug but for some reason 'improvement' isn't an option which just confuses me.

The entity attribute FOLLOW_RANGE loads all chunks in a block radius of that range.

This is displayed in NavigationAbstract.a(Entity) where it creates a ChunkCache.
Now I see huge room for improvement because you never have to load a square radius around a player when you are just moving towards an entity in already loaded chunks. You just need to load the chunks between the two entities.