There are plenty of regulated stablecoins [1]. Hell, my state is launching one [2].
Governments usually have to subpoeana banks to get transaction records. With a stablecoin, those records are centralised.
[1] https://home.treasury.gov/system/files/136/StableCoinReport_...
[2] https://www.ledgerinsights.com/state-of-wyoming-plans-stable...