El Salvador already uses the US dollar, but it has no control over what the US does to its money supply.
Imo you're just trading "beholden to the usgovt" with "beholden to miners, whales and wall street" plus wild price swings. Former or latter may be preferable for certain reasons, but for fiscal stability or day-to-day use the choice seems obvious to me.
The price of BTC, even today, seems very easy to manipulate.