It might be worth noting that this seems more to do with why different transistor types are being used (fin-fets, nano tubes, etc) since we really haven't reach

It might be worth noting that this seems more to do with why different transistor types are being used (fin-fets, nano tubes, etc) since we really haven't reached the physical limit of "traditional" transistors yet. I'd also argue that the motivation behind quantum computers is very much unrelated to limitations on transistor sizes, and more about the algorithms that can potentially be much faster than on traditional logic, such as shor's factoring algorithm