By now most of you have heard how poorly Monster Hunter runs on even the mightiest of computers, here's the half-assed non-answer as to why.
To eliminate interstitial loading during active gameplay, MHW loads the entire level into memory. In addition to managing assets loaded into memory, it keeps track of monster interactions, health status, environment/object changes, manages LOD & object culling, calculates collision detection and physics simulation, and tons of other background telemetry stuff that you don't see yet requires CPU cycle. This is in addition to supporting any GPU rendering tasks.
