A MKII/USBC version would not feature USB hosting. So audio to another device would not happen. But even if it did it would still be worse than using the analog output due to latency. USB is not better than good ole analog when it comes to simple audio just working like we expect it to.
When there will be a MKII it will be more about the hardware than any changes that would make features incompatible with the current hardware. There have not been significant improvements in chips to warrant more power under the hood without switching to a raspberry pi or some linux in a box solution which has itās own set of drawbacks. Furthermore the sample without playing samples limitation (because it is not using large external RAM) also makes features like never have to wait for the loading of a song or sample possible, which is part of the joy.