There is a lot of infrastructures to be built.
More importantly than building a decentralized exchange is the fact that it needs to NOT operate through the US soil, systems, banks, credit unions, or money transfer systems.
All of these things are monitored.
If you're a US citizen, then any "income" (as it's currently enforced and defined by the Internal Revenue System) you get from anywhere else on the planet, in any denomination is considered to be possibly taxable.
Regardless of the monetary system chosen or worked, great care needs to be taken in protecting it legally from the abuses described by the OP, regardless of the country of origin perpetrating it.
I'm not advocating for illegal activities to be shielded, but simply that freedom of choice is protected. Since Asgardia is being built with the eventual goal of being self-sustaining independent of any other country, these things should be considered at the Architecture phase.