Horan is not claiming those things. Horan is wondering if the experts have considered those things. Scott's hand waving answer suggests that "no the experts have not." Engineering professionalism entails formal assessment of the risks. The burden of proof is on the engineer. Without that, it's astrology not engineering.

Quoting Horan:

But how close does the hand on that doomsday clock move to midnight once we “can harness an exponential number of amplitudes for computation"?

Looks like a claim to me.

but it ends with a question mark?

Implicit in the question.

Yeah, you're right.

It's a standard trick to sound smart. Just ask if the new thing have some unintended consequences. What is the cost of asking this for every new technology?

Relevant xkcd https://xkcd.com/1215/