A lot of effort has been spent studying trust. I'm not clear how a PO Box creates trust.
How do you trust that food from McDonalds is safe? How do you trust that Samsung hasn't empowered parties to control the mic on your phone? How do you trust Wells Fargo to hold your deposits? How do you trust the kennel to walk your dog?
Trust is really really hard. So a lot of people choose to adopt a zero trust philosophy.
Except they still eat at McDonalds and buy Samsung and bank at Wells Fargo. But they drop their dog off with Aunt Lawana now, instead of the commercial kennel.
Do you remember when Sony installed rootkits? Do you remember when Windows got compromised every 5th day for two years straight? Do you remember when HP broke every HP printer with a firmware update? Do you remember when the whole world got put on pause because an "anti" malware software pushed a flawed update? Do you remember when a certain credit-rating bureau got breached and exposed the PII of, well, everybody?
Do you remember that every one of these companies went on to post record profits?
My personal take is that we need a society with a lot more trust.