Found the solution. Lowering graphics quality in settings stops the crashing, it seems that somehow, it was possible to lessen the performance of this game even further than the previous update.

In short, game can no longer handle its own medium-high graphics settings, and perpetually crashes. Good job, toss it in with the god mode and rendering problems!!

Never mind, either more complicated or unrelated. Crashes still occurring with or without controller, across any server

Discovered it has something to do with controller input. Loading into any M&K server with controller unplugged from PC, no crash. Plugging in the controller after loading in, no crash. Loading into any server with controller plugged in, instant crash 👍