Current Social Security retirement benefits should be paid for, on a means-tested basis, with progressive general federal taxes, not with regressive payroll taxes.
Why?
The only justification for using regressive payroll taxes to pay benefits was the existence of the social contract whereby the payer of the tax could expect a corresponding benefit. The quid-pro-quo nature of taxes and benefits justified departure from the general rule of funding with progressive taxation.
Now, even the Social Security Administration acknowledges that full benefits cannot be paid to current workers who will be retired in 2032 (2034). The social contract is broken. The moral justification for use of regressive taxes is gone. Using regressive payroll taxes to pay current benefits is immoral.
