Take this thought experiment: imagine you're given the opportunity to purchase a crypto like BTC for say 20 grands per BTC. Even if you don't believe in the business model of crypto, you would jump on the purchase (irreversible being a nice feature) then you'll immediately flip it (liquidate it) on the open market, for a nice profit, right?
Now think about the general case: you pay a bit less than the going price in the rest of the world, to take into account the problem of "where the cash come from" (certainly not a difficulty for a country with as large as Argentina, with multiple land borders and sea ports) and price in the cost of solving this problem. Given the right price, you'll find clients, as every trade needs a counterparty, for a mutually beneficial exchange.
Basically crypto is a way to scale up illegal financial activity? One trader has a way to get money in nobody asks questions about and is able to capitalize that ability.
The laws of Argentina do not matters to us in the US: if some company wants actual dollar bills to distribute them in South America, can prove the source of their funds is trading crypto, and pays for that service, who are we to tell them "no, that's bad, I won't do business with you".
It's a good thing for everyone - including the people in Argentina who get to enjoy the Blue Dollar by receiving more from the remittance.
BTW It's quite frightening to see replies likes yours. Most people here on HN seems to have a blind admiration for governments and laws, with about 0 critical thinking abilities when it comes to policies that are ultimately harmful (for ex, based on what I read here about Wise etc, I'd summarize the default HN position to "let's make our apps obey currency control laws in Argentina, even if it further impoverishes the locals!") until they are ultimately proved pointless (ex: turning back Australia into a prison island to control a virus as contagious as the smallpox... yeah not gonna work, but thanks for demonstrating that)
I'm admittedly very uninformed when it comes to Argentina, but the point is that tracking down the entity that is paying cash for coins cannot be that difficult. Even the most inept governments in the world typically become very efficient when it comes to money.
Now think about the general case: you pay a bit less than the going price in the rest of the world, to take into account the problem of "where the cash come from" (certainly not a difficulty for a country with as large as Argentina, with multiple land borders and sea ports) and price in the cost of solving this problem. Given the right price, you'll find clients, as every trade needs a counterparty, for a mutually beneficial exchange.
And you then have the answer to your question.