Why can they not just use America's banking infrastructure directly instead of using America's banking infrastructure indirectly through meaningless overengineered abstractions like stablecoins?
I am not an expert but I don’t believe most countries would allow their citizens to use American banking infrastructure, nor would most American banks accept a foreign account. Stablecoins get around these limitations, while also providing lower fees and higher availability.
How do they open the bank account? Looks like a foreigner opening a bank account in the US would need proof that they have a US address. (Or at least, the major banks I checked did.)