The paper explains it more as an experimental process than a manufacturing process. Each granule of hiroshimaite captures a "unique" micro-environment. One could imagine an ethical version of this involving conventional explosives in a controlled environment containing a variety of metallic samples of different compositions.
Metals refining in space or a no atmosphere place like the moon. If an alloy is discovered that has properties we want I can see some future civilization popping nukes like pellets to produce it.
There were some nuclear fracking experiments where the nukes cost in the range of a few hundred thousand dollars. It's probably cheaper than you think.
I mean, I'm probably just being contrarian and I too would appreciate it if people stopped suffering, but like, people are suffering worse than that right now as we type this.
They did not get vaporized in the fireball. We have survivors at the hypocenter. Intense burns and radiation poisoning killed most plus conventional blast damage mechanisms. Half the acute deaths happened after the first day.