I believe that the maximum any now-retired person could have paid over their working tenure only amounts to a few years. Four is close as I recall; may be exactly right. What is certain is that even the people who paid the max every year will be collecting welfare off your and my check.
There is a lot more to it than a simple addition of money paid in vs. money received.
If the money paid in were placed in a bank account, the interest earned over the years would be more than the total funds deposited.
If the money were invested in accordance with any type of view toward modern portfolio theory the returns would be even greater.
I would much rather have the real value of what I have contributed, with interest, than a promise of some kind of payment from the government.