The US has an exit tax if you renounce citizenship, and it's assessed on your entire net worth. If the article you linked is accurate, this german tax seems much more reasonable.
EDIT: actually, I reviewed, and I think it's broadly similar --- treat all assets as if sold at market value on the date of exit. Thus, any deferred taxes from unrealized capital gains need to be paid when you exit the taxing jurisdiction. Although, again, if the linked article is correct, it only happens to assets where you own >= 1% of the company when exiting Germany, and all capital assets if you qualify in the US.
[1] https://www.winheller.com/en/tax-law-tax-advisory/internatio...