It will be a huge Opportunity Loss. Plus the way the world is shaping up, you will be better off with the country's Economic/Financial/Military Systems behind you.
If you can replace your American passport with a Canadian, Australian or Singaporean passport, it's not too bad: people from these countries have an easy time getting a visa to work in the US. [0] All while not being subject to American taxes while outside the US.
> Plus the way the world is shaping up, you will be better off with the country's Economic/Financial/Military Systems behind you.
Eh, it's a two-edged sword. On this aspect you are probably better off with the passport of a country that's clearly in the Western sphere, but also one that no-one actually hates. Think Canada or Switzerland.
[0] Though I don't know how well that works for former citizens?
Counterpoint: having a US passport has made securing banking very difficult as a lot of places don't want to deal with the IRS. It's been impossible for me to get an account on a local currency crypto exchange well because they don't want to deal with the FTC rules. The last one I looked at, their FAQs included a special place to upload your US citizenship renunciation forms. A US passport puts you an a lot lists with Syria, Yemen, Iran, etc. (and one could easily argue the US as a terrorist country).
What support can he expect? under what circumstance? (hint-- it might be less than you think)