The concept of flying out to distant asteroids and mining them for precious metals is going to seem preposterous right up until the moment that someone actually does it.
It’s a terrible business model because it requires years and years of up-front investment and solving myriad technical problems before there’s any hope of a financial return. And scooping up material from a rock pile in space is a lot more challenging than mining the Earth. Asteroids are typically millions of miles away, moving tens of thousands of miles per hour relative to the Sun.
Good luck.