So, they can't buy Bitcoin, but they can buy 20 billion dollars worth of Argentine pesos...
Discussion
Gotta keep the fiat wheel turning
The crux of the biscuit is in the swap. The terms aren't clear yet, but the currencies must be swapped back (likely with interest on both the US and argentina's part).
I don't mean to defend this fiat swap (or argue with your pemise as I also wish they'd start purchasing bitcoin) I just thought I'd chime in to clarify that it's not a direct 'purchase' ... the US won't be able to use or rehypothecate the pesos and they will be paid back (possibly with interest) at a specified time.
There are geo-political reasons to extend this offer as well, like combating China's influence in the Americas, stabilize market production of rare earth's, etc.
they don't *need* to buy bitcorn because the Treasury Companies are subject to their grab ass and will give it up.
Meanwhile Argentina is geographically super-valuable
Sí. Now my pesos will buy more sats.

It's just a swap line to bail out Scott Bessents old Hedge Fund buddy, from back when he worked for George Soros. No big deal. Normal practices for central banks, basically the reason they were invented.
Pesos man. They’re going up forever
