It never was about the battery being out of the device or being completely dead…in fact, the only known way to keep them from bricking themselves in the long run is to pull out the battery of a functional unit. The scenario that broke the sensors was not a dead battery, but a low battery. With a low battery, there was always a chance that the next motion event would cause data to be rewritten internally in a manner that permanently corrupted the on-device mac address…and so the longer the device was in the sate of low-battery, the greater the likelihood it would happen. Wyze never told users how low was too low (in fact, they never told users anything about the problem at all).
I think it only affected the contact sensors - at least that’s the only type that I experienced this problem with - of my original fleet of 2 motion sensors and 10 contact sensors, all but 2 of my contact sensors bit the dust, but both my motion sensors were still working right up until I abandoned wyze sense products in favor of something else.