I suspect that flooding the market with those metals would depress the price of those commodities significantly.
What could we build if titanium was free (or very close)? What would our houses and cars look like if there was a limitless supply of aluminum?
A vital step to us getting off this planet in a meaningful way is sending robots out to gather resources, both to build the ships we'll need outside of our gravity well and to return some of that abundance to the surface so we can alleviate our scarcities here.
There IS a limitless supply of aluminum. The top kilometer of crust all over the earth is stunningly rich in aluminum. It's just that PROCESSING it takes energy.
...just like processing an asteroid.
Dirt, though, has the added advantage of already being HERE.
As I recall, the allure with metals in asteroids that they are "hunks of cut up planets". Instead of digging and processing, you just scrape the good stuff off the surface and (being in deep space and all) its not oxidized or otherwise contaminated like it is when found on earth. You build your kickass starship out of it right then and there or encapsulate it in some heat shielding and drop it in the nearest ocean for retrieval.
A great many people who bought a bunch of gold as a hedge against inflation might be disappointed though...
It would still take some processing to separate the compounds, but nowhere near as much as ores.
Which is exactly why we need fusion power and not the hydro, wind and solar power the shortsighted environmentalists keep pushing. Those will never produce the vast additional amounts of energy needed to make the next step in our general wellbeing. With cheap limitless energy, you can produce all the water you want, bind all the CO2 you want, produce all the O3 you want, recycle everything you want and even use fission to produce whatever materials you want.
Seriously, do the math, for the applications we're talking about (asteroid mining), given that the solar constant at earths orbit is roughly 1400 Watts/m^2 a relatively modest set of mirrors could be used to heat metal up to working temperature.
Because fusion scales well. With time, everything limited by technology becomes cheap as technology advances. There are no fundamental problems or limits in fusion, just practical problems. Fusion has never received the amount of funding it should have received. How long did it take ITER to get the measly 10 billion dollars required?
As for fission: the all important difference is that the fuel for fusion is much easier to get, is unlimited and the garbage that gets left behind isn't nearly as much of a problem. Moreover, there is no risk of blowing up half the nearby city and irradiating the area for the next 100K years. Fusion and fission are incomparable as for their ability to provide energy.
But yeah, to consume that much materials would take entire worlds, colonized.