

NASA funded SpaceX based on hitting milestones on their COTS program. Those were just as available to Boeing and Blue Origin, but they had less success meeting those milestones and making a profit under fixed price contracts (as opposed to the traditional cost plus contracts). It’s still NASA-defined standards, only with an offloading of the risk and uncertainty onto the private contractors, which was great for SpaceX and terrible for Boeing.
But ultimately it’s still just contracting.
A 56.6 kbps modem just needs an analog audio channel to work, right? A stereo jack has two channels for full duplex communication at that point.