It still matters who holds your data. Yes they can't read it, but they can hold it ransom. What if the US decides it wants to leverage the backups in tariff negotiations or similar? Not saying this would happen, but as a state level actor, you have to prepare for these eventualities.

That's why you backup to numerous places and in numerous geopolitical blocs. Single points of failure are always a bad idea. You have to create increasingly absurd scenarios for there to be a problem.

or… hear me out…

you obviate the need for complex solutions like that by simply having a second site.