One shouldn't use a locked down device to auto share pictures and approve children app install requests. If there is no need for a separate device for sensitive data then one possibly is not a person of interest and doesn't need a lockdown mode. It is not possible to have comfort and security at the same time.

And a sensitive device should not be easily discoverable to gatekeep who can actually send anything to it. This is also renders it unusable for day to day family tasks.