Social Security is not "a mandatory way of saving for retirement," that's a bullshit way of looking at it. You are not putting money into an account, and getting that money back when you retire. It 100% is a tax. Tax is not a bad word. It's a social safety net, payouts should be capped, but contributions should not be (or if they are, it should be much much higher).

That's how functioning societies work. They take care of their old and infirmed.