According to the keynote, AW series 3 will support a limited list of carriers at launch so I'm curious as to how the eSIM which AW3 uses is implemented? Looks

According to the keynote, AW series 3 will support a limited list of carriers at launch so I'm curious as to how the eSIM which AW3 uses is implemented? Looks like users on unsupported carriers depend on Apple to enter into a commercial agreement for cellular to work with their carrier?