the capital markets would never invest in anything but themselves.

The "capital markets" are not closed. The "market" itself doesn't decide what to invest in -- individuals and corporations do.

I would expect an individual/corporation armed with real "super intelligence" to have a distinct advantage in this regard --- wouldn't you?

What better way to prove the value of AI than applying it to earn mountains of money in the open market --- instead of setting mountains of the stuff on fire.