Truly impressive work, although this may explain why the game struggles with performance. According to data_stash, nearly 1,000 bones are used in the armature, probably examined using RE Mesh Editor.
Here are some more neat details from Monster Hunter Wilds:
Just a few days ago, Capcom rolled out Title Update 4 for Monster Hunter Wilds, focused on long-awaited performance improvements across all platforms. In January, a PC-focused update with further enhancements is planned, with more optimizations expected in the February update.