We already allow freedom of movement from countries within the EU, whose population sizes are an order of magnitude more than ours. Yet the amount of paperwork it takes for a US citizen to work here is fairly high. They also don't get any unemployment benefits as long as they are on a work permit because of NAV's rules.
Why should the US offer us more than what we offer them?
Swiss banks routinely either reject Americans, or ask for so much paperwork.
Which frankly speaking should be rejected due to Congress reneging on their side of agreement.
To be clear: The issue with FACTA is that saying "yes" to an American citizen (or national) adds costs to the foreign bank (in free labour on-behalf of the US). The US doesn't fund any of the work of reporting these accounts back to US.
Its almost as if the US has internal sources of free labour and expects no repercussions from expecting the same from their international counterparts...