Banning TikTok from the U.S. is really just banning them engaging in financial transactions in the U.S. Asking Google or whoever to poison DNS in a country is a whole different technical ball of wax. The two are not comparable. One difference is that ByteDance won't attempt to engage in financial transactions in the U.S. because doing so would create a diplomatic crisis and anyways it's not easy for a company of that size and with that much business to evade sanctions like that. While the pirate will and can just due to their small size and their ability to set up new bank accounts, which is why countries try to block pirates in the network rather than in the financial system, but blocking them in the network is pretty difficult, and blocking them in DNS -DNSSEC be damned- is basically the easiest way.
The US ban banned app stores from providing their free applications, which is just as much as a technical choke point as DNS and nothing to do with financial transactions.
