The value isn't on earth. It's real value is in it's location.
It costs $3000 or so to send a pound of water (or anything) to space. If it's already up there, and not in earth's gravity well, it's a whole lot cheaper.
Gold and platinum and all that crap is just gravy.
Consumables are where the value lies.
I wish the articles on the value of asteroids would point that out.
I’m not sure I get your point. Everything we need is here. Why do we want to be in a different location.
I understand the principle of diversification but we aren’t getting to another star system and being in the asteroid belt isn’t going to really help us if things to seriously wrong in the Sol system.