> Why is it unjust when literally the entire U.K. population is in support of this position?
Obviously not "literally the entire U.K. population" if someone in the U.K. isn't following the rule.
This is a complex subject and I'm not going to get into it here, but the Cliff's Notes version is basically that the U.K. government is not a party to this transaction, is not harmed by it, and does not represent (as in: having a formal, revocable agent/principal relationship with) anyone who is either a party to the transaction or harmed by it, and thus has no standing to interfere. The justice or injustice of the matter is unaffected by whether the government's interference would be popular.
Put simply: your logic is insane and no government adopts it, for good reason.
Longer version: governments adopt rules based on what works for them and their population. This includes rules that govern what can and can’t be sold in a business transaction. This is a principle as old as government itself. It makes sense that governments then apply these rules to things going in and out of its borders. It would be nuts to ban the sale of guns inside a country but allow them to be sold into the country, for example.
> This includes rules that govern what can and can’t be sold in a business transaction. This is a principle as old as government itself.
If we're talking about a "business transaction" as in an exchange of physical goods across the border, then I agree. I said that it was unjust, not that it was without precedent. You seem to be under the mistaken impression that I believe in the concept of government itself. The core of what government is, and does, is unjust. Arguing that governments have always done things this way carries zero weight with me.
Applying these rules (or any rules) to the non-commercial exchange of information, or even to commercial services involving no exchange of physical property, is the recent, and more immediately concerning, development.
> It would be nuts to ban the sale of guns inside a country…
I agree with you up to that point. But if they want to ban the import of "wireless handheld hold punchers" or any other contraband they should do that at the border, by stopping the shipments—which at that point consist of the buyer inside the country attempting to import their own property after the sale—and not by attempting to impose their internal rules on foreign sellers. Residents could buy them but would have to keep them outside the country, perhaps using them only while visiting the country the goods were in at the time of the sale, or somewhere else where they are legal.
Obviously not "literally the entire U.K. population" if someone in the U.K. isn't following the rule.
This is a complex subject and I'm not going to get into it here, but the Cliff's Notes version is basically that the U.K. government is not a party to this transaction, is not harmed by it, and does not represent (as in: having a formal, revocable agent/principal relationship with) anyone who is either a party to the transaction or harmed by it, and thus has no standing to interfere. The justice or injustice of the matter is unaffected by whether the government's interference would be popular.