I spent most of today trying to figure out why some of the monsters in the Monster Hunter Wilds beta look like bundles of mating pyramids covered in alligator sauce. Nic had previously tipped me off to this reddit thread talking about anonymous Chinese players allegedly datamining the beta's monster models, and learned that they were extremely large, spanning hundreds of thousands of polygons.
If every monster in Monster Hunter Wilds was always this fancy, your computer would turn into a volcano. That's why the game resorts to optional loading systems to ensure that you only see these amazing details when the monsters are nearby and sitting angrily on you depending on the situation. As they move further afield, decorations are reduced to free up memory and processing power. The popular Redditor explanation for the existence of Henry Moore statue-like monsters is basically that LOD systems are forgetful and neglect to load additional polygons nearby.