I would understand creating a reserve in a stable asset. Maybe the goal here is to stabilize bitcoin by attaching it to the US economy, in which case it skyrock

I would understand creating a reserve in a stable asset. Maybe the goal here is to stabilize bitcoin by attaching it to the US economy, in which case it skyrockets and billionaires can now exit, leaving all taxpayers as bag holders without any of the potential upside of holding actual btc. But, if all of a sudden the US govt holds BTC, then it becomes cash equivalent, and all banks will start letting people cash out and bitcoin will then fully enter the economy as a first class citizen. Banks will put a ledger in front of their btc deposits and give you BTC credit/debit cards that run on Visa/Mastercard's network and let you pay for stuff without actually moving anything on the blockchain.