I'll concede the point, it likely is many years away. Similar to commercial fusion reactors in that sense.

But I do think we'll see it once the economics make sense. Things are moving in that direction. Easily mineable precious metals here are diminishing, and this will drive up cost of extraction. At the same time we are now seeing commercial involvement in the space industry, with some quite rapid development. The potential rewards from asteroids are - sorry - astronomical. Once the cost of getting at them and returning to Earth ceases to be prohibitive, then asteroid mining becomes inevitable. But yes, likely some way away yet.