No, not even close: most expats do not pay social security taxes abroad. If you work for the USA embassy, you pay SS tax, but if you work for Microsoft China, you do not (you do, however, pay Chinese SS of course). In particular, see https://www.hrblock.com/expat-tax-preparation/resource-cente...

> If you are working for a foreign employer who has no requirement to withhold U.S. social security, you have no obligation to remit U.S. social security taxes on your earnings and in fact, are prohibited from making such voluntary contributions to the U.S. Social Security System.

Almost every US company has it setup that you are going to be working for a foreign employer, not a US one.