You don't have to pay taxes nor social security for 20+ years in order to become a citizen in very many countries. You can live on benefits before becoming a citizen and after becoming a citizen. Usually the requirement is that you are a resident for a set number of years in order to become a citizen.
reply> You can live on benefits before becoming a citizen and after becoming a citizen
replyWhat benefits? I don't know every country in the world, in Germany unless you count retirement as a benefit (which is something you pay for and have to reach a certain age that is ever moving upwards) you don't get any assistance if you're not living in the country.
When was the last time you were called to personally appear and report to the German government, so that they could verify that you are in the country, and not somewhere else?
replyBenefits aren't collected in cash, they are sent to bank accounts. The beneficiary can be anywhere.