The size of the limit falls every year as it's not inflation linked or FX adjusted. When it was first set it was truly very high and over time it's fallen to the point where now a pretty typical skilled job in a place like Switzerland will immediately push Americans over the limit.

Also, tax is complicated. Other countries often have mandatory pension or savings schemes for unemployment and these are not always recognised as such by the US tax code, meaning you can get taxed on your pension twice, etc.