Well, then the solution is to get a PO Box, but only give the PO Box as the delivery address for consignments that seem that they may be likely to be too large to fit in the regular delivery box. This should take care of about 99% of the problem, though I can’t gurantee that nobody will send an unsolicited refrigerator to their home address.
I’m a retired letter carrier. When I started, my postmaster told me, “We have right of entry, but if a patron objects we honor that.”
Also, we were instructed to leave a notice anytime there was a package too large for the box and no one home to receive it…even if it didn’t require a signature. As a practical matter we left packages if there was a safe place to leave them or if we’d arranged a spot (like the back porch, or between the doors) with the customer.
Of course, this was in the time when a mailman commonly had a route for 15+ years and knew his customers.