These can be done pretty quickly and cheaply, both because the cost of access has dropped, and because the customer actually wants them, not a jobs program. ISS has warped our notions of what space stations have to cost and how long they should take to build as much as Apollo has about how much going to the moon has to cost.
They’ve been courting a lot of American companies with money, but as with Luxembourg, there are strings attached. The investment requires that the companies locate there. Pretty sure I’d rather live in Luxembourg than the Emirates, though.
There are large lacunae in the Outer Space Treaty, and as the article points out, it would be absurd to send someone to Mars to arrest someone per Article VI.