Currently, VRChat's IK2.0 will limited connected trackers to a max of 8 tracker pucks in SteamVR ( + 1 HMD and 2 hand controllers). Specifically, it picks the first 8 tracked devices in SteamVR that aren't the HMD or hands. This makes it unnecessarily inconvenient when your VR setup has more than 8 additional tracked devices for whatever reason (example: VR gloves using Opengloves driver) and you want to use the new IK to its fullest potential.