I am certainly not at the level of needing or desiring this level of protection, but I point out / ask one question: I understand iPhones (and maybe iPads) act

I am certainly not at the level of needing or desiring this level of protection, but I point out / ask one question: I understand iPhones (and maybe iPads) actually do not fully turn themselves off any more even when "powered off". Is it then possible that even before a device is sold to you, its history is known somewhere and you're not getting a "clean" absolutely untraceable unit?