2. It's practically impossible to run a payment processor in the U.S. without getting funds frozen. PayPal is as successful as it is in part because they built a giant machine-learning monstrosity to automatically detect and deal with fraud (and it's full of false positives, but they consider that just a cost of doing business on the U.S. Internet).
1. There's a very high regulatory burden.
2. It's practically impossible to run a payment processor in the U.S. without getting funds frozen. PayPal is as successful as it is in part because they built a giant machine-learning monstrosity to automatically detect and deal with fraud (and it's full of false positives, but they consider that just a cost of doing business on the U.S. Internet).