This is interesting! The article indicates that one of the big issues with quantum computing is the approach for handling errors that are inherent in the process. I wonder if there is some kind of Information Theory based limitation that in some way parallels what happens in the area of digital communications. Digital communication rates over noisy channels are subject to Shannon’s Limit, but it takes a lot of sophisticated coding for error correction, and the associated processing power, to get anywhere close to this limit. Such sophisticated techniques have become practical only recently, and have been applied to the area of satellite data communications only in recent years in order to enable higher levels of modulation that can increase the resulting data rates supported, but only if the error correction techniques can handle it. (As you get to higher levels of modulation, you are tending more towards an analog means of transmission for the digital data, which feeds into my argument that we human beings are force-fitting digital into an analog world, but that is a subject for a different discussion.)
Might it be that there are some fundamental concepts that are similar and hold true in both digital communications and quantum computing technology? How fast is it theoretically possible to go with quantum computing, and is the limitation due to quantum constraints, or noise, or some combination? Can we make digital computing approximate an analog process in some way? Is mathematics an analog process? Inquiring minds want to know!