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.
So if your threat model includes the sort of attacker that has a phone exploit or the ability to confiscate it, you should not be using FaceID. Instead, consider using six digit PIN with auto-delete after 10 attempts. Also enable Lockdown Mode And if you use iCloud, enable Advanced Data Protection.
Any savvy user can download it for free. I used it recently to create a profile for a friend I’m working with to configure their email account.
If you’re the tech person for your friends and family, Apple Configurator is quite handy: https://support.apple.com/guide/apple-configurator-mac/intro...
I had to create a shortcut to actually trigger a reboot, as I couldn’t find a reboot option in settings. My iPhone 13 mini on iOS 17.7.1 took 29 seconds.
In environments where shoulder surfing is a concern, I prefer to use the multiple profiles feature: log out of my main profile (which is actually a secondary profile) to completely evict its keys from memory, and switch to a burner secondary profile containing no personal data, which unlocks with my fingerprint for convenience.