Incidentally this is why I use .eu
It wouldn't be prudent to build a business/brand/reputation on a domain name where you've intentionally registered it to a false identity.
To me, the penalties are only one of the concerns - how you'd deal with someone attempting to hijack your domain when you've faked the ownership records is a problem too.
a PO Box address
In the U.S., some/all post offices have added the option of real "street addressing." Before, you'd have to use PO Box 123, City, State. But with street addressing, now you can use - say - 45 Main St #123, City, State.
Non-USPS places have had this sort of thing for a while. Some will even "let" you call it "Suite 123" - despite it being a small metal box with not much room for furniture. (I think the "letting" part is more them just not caring, and only looking at the numbers. It's not impossible but I'd be surprised if there were actual laws covering that. Though it could be a factor if something like fraud were being committed. IANAL.)
No. They will require PO box providers to be accredited with ICANN and subject to all these crazy rules, giving you no privacy.
> Alternatively, one could enter information that looks plausibly valid but is in fact completely invented.
This is exactly what all the real crooks will do, but you and me will not be able to, because we don't want to lose our domains.
Well, I'd be very interested to see how ICANN could get post offices, like the United States Postal Service or Royal Mail, to go along with submitting to ICANN accreditation. That aside, data on people who own USPS-provided post office boxes and boxes held at commercial mail receiving agencies (CMRAs, like the UPS Store, and so on) can be obtained from the USPS, per 39 CFR 265.6(d)(5)(i) through (iii):
(i) To a federal, state or local government agency upon prior written certification that the information is required for the performance of its duties.
(ii) To a person empowered by law to serve legal process, or the attorney for a party in whose behalf service will be made, or a party who is acting pro se, upon receipt of written information that specifically includes all of the following: (a bunch of things)
(iii) In compliance with a subpoena or court order, except that change of address or boxholder information which is not otherwise subject to disclosure under these regulations may be disclosed only pursuant to a court order.
Are all of their domain names registered properly? Shall we start sending them A LOT of mail explaining these consequences?
ICANN is only the authority because we all said they are the authority. Do you know the fight that would break out if we lost faith in ICANN and multiple firms in the right economic place who know the right people at the right time provided an alternative authority? The switch to ipv6 is already weakening ICANN authority. The value of an ip address is decreasing.
We have to trust someone. End users are not gonna type in ip addresses human brains just aren't wired like that. But talking with any government is not cool. ICANN is a trust all citizens of earth currently agree on. ICANN is the global diplomat they need diplomatic immunity - and need not abuse it.
What makes you think that? ICANN's requirement is that you provide a valid address you are contactable at. A PO box fulfils that requirement.
Alternatively, one could enter information that looks plausibly valid but is in fact completely invented. How often does one receive articles in the mail or phone calls to the whois contact points anyway? As far as I've experienced, any communication is to the email address. I suppose it depends what the penalties are if you're somehow found out.