The most natural evolution forward would seem to be processing with unconventional quantum-effect phenomena, probably operation specific (addition, multiplicati

The most natural evolution forward would seem to be processing with unconventional quantum-effect phenomena, probably operation specific (addition, multiplication, ...). So not quantum computers in the sense of implementing quantum circuits, but rather opportunistic exploitation of quantum effects. These foundries and manufacturing equipment companies would logically sit on their insights as it might turn out to be a slow but steady march towards miniaturized quantum computers eventually. Think of how thick towels started as a manufacturing defect: a machine in a conventional cloth factory had a part break down, and instead of churning out the usual flat cloth it erroneously wasted a loop of yarn at each 'weave' (for lack of better words as I'm not into weaving). Having no immediate solution at hand to recover the yarn from the thick cloth was sold / distributed as scrap. The problem of the machine was identified and fixed. The users of the cheap scrap came back for more as they discovered the superior water absorbing qualities... Since the fault was documented they could intentionally reproduce the desired 'faulty' cloth.