I wouldn't assume this is explicitely to help LEO, but more because this is (AFAIK) the first time this is being trialed by Apple. 72 hours is a touch long, IMO

I wouldn't assume this is explicitely to help LEO, but more because this is (AFAIK) the first time this is being trialed by Apple. 72 hours is a touch long, IMO (and based on some comments, it's not just me), but when your update touches millions of devices, it's also best to test thoroughly and have the first iteration be too long rather than too short. It's easy to drop the 72 hours in a future update, or tie a shorter delay to (as I believe Apple calls it) Lockdown Mode - the more important thing might be to keep the "It just works" assumption most people (myself not included) seem to have vis-a-vis Apple products. Notably, I assume it will never be user-configurable directly. Possibly through Lockdown Mode ("If enabled then shorter delay"), but I wouldn't count on Apple adding an explicit setting.