As discussed in the Animation&Rigging module meeting (https://devtalk.blender.org/t/2022-12-08-animation-rigging-module-meeting/26818) the "While Held" (called POSE_PROPAGATE_SMART_HOLDS in code) can be removed.
It doesn't do anything meaningful.
Depends on T87548
We concluded the removal of the code shouldn't be in the same patch