This is definitely what America is going for and definitely not the way things are right now. It’s very much possible to leave and or or move money legally.
If you own a holding company in another country, you need to declare that and be taxed on it in addition to that country's tax.
I know this because I own a business and wish to live abroad so I really would like to leave but I can't.
I agree once you’ve built up a bank account as a us citizen it’s quite hard to. But if you saw this coming, you could easily have an XYZ USA, an XYZ China, etc.