The problem is that it wouldn’t be just ‘some kind of breakout board’. The OT chipset is said to not be able to transfer audio over USB. That means a complete redesign (instead of a simple modification), in order to implement Overbridge.
It seems to me that Overbridge is promoted by Elektron as a route to get the analogue signal processing in the AF/AK and AR integrated into a computer-based setup. As others have pointed out, there are already many other ways to do digital processing on a computer.