Let’s start with a simpler question that involves no hypotheticals: Why do a group of people have an interest in maintaining the blockchain for another block? Why are they interested in continuing something that’s been dead for 10 minutes (the block update time)?
(Partial) answer: The new blocks are created by the miners. The miners are interested in mining because bitcoin has a value per kWh that’s better than their alternatives. Bitcoin has value because [???].
I don’t fully understand what [???] is, but in order to show that the value of a BTC wallet can be permanently damaged by USG, you’d have to explain to me why [???] disappears after 2, 20, or 200 years, but not after 10 minutes.
One of the reasons in [???] is that BTC has value as a medium of exchange, and insofar as this is true, the value comes from the people who own/use it. Those people strongly prefer to keep using BTC, as opposed to switching to another currency. [By the way, this is why I didn’t define “them”: it’s kind of murky, because it’s the miners who maintain BTC directly but it’s the users/owners who bear the responsibility for making it valuable].