The US does not have an exit tax for businesses, but has an absolutely horrible tax system in which expats are treated badly.

The reporting requirements for expats are insane: all bank/brokerage/whatever accounts with max levels during the year, FATCA and FBAR forms, and the cherry on top: Form 8858 ("Foreign Disregarded Entities", whatever that is) which is needed for your self-employment and for each of your rental properties. If you think this is easy, look it up — https://www.irs.gov/forms-pubs/about-form-8858

It's pretty much impossible to file your taxes yourself, you will never get it right. You have to pay specialized accountants, some of which will charge you >$1500 to prepare a yearly return with self-employment and rental.

Then come the actual taxes to pay, which are the least of all problems.

Expats are treated this way because they have no lobbying power.

I can confirm this from experience. The instant your situation becomes more complicated than "I work one full time job and have no investments to my name whatsoever" you are in for a brutal time without an accountant by your side.

On the other hand, if you do have an accountant by your side, you potentially expose yourself to some of the most powerful labor arbitrage on the planet as a tech worker. Making $100k remotely from the US might sound like a bad deal until you live in a country where the average wage is $20,000. Like all things US tax wise, you are disproportionately rewarded for being clever and reading a lot.

US totally does: https://www.irs.gov/individuals/international-taxpayers/expa... - long-term (8y+) green card holders may need to pay up.

One big difference is that the clock only start ticking after you get green card, whereas with Germany any residence year counts. Oh, and citizens of course aren't affected - since US continues to tax them wherever, but Germany like almost all other countries practices residence-based taxation.

Not to mention pfic rules making simple index investing impossible.