Why is everything in this game so damn aggressive?

Do I really need to be chased 3 miles by every porcupine, crane, turtle and mouse that I run by? It is infuriating. There's no reason I shouldn't be able to walk 5 feet without being aggro'd by ANOTHER mob due to how densely packed these rabid demons are. Mining, herbalism and fishing get interrupted constantly because a bird happened to notice me from 500 yards away.​Rant over. Jesus.