VRCHeadChop components have no effect on any non-humanoid avatars.

I tested multiple avatars and settings. The bug occurs with or without custom animator layers, so it's not an issue with animations overwriting anything.

Given how important this component is to most non-humanoid avatars, this seems like an unintentional error. The workaround of including an entire humanoid-skeleton is poor for both optimization and user-friendliness.