One of the reasons why the more well off people don't like Social Security and want to sabotage it is that the way benefits are calculated favors the poor.
A lot pf people don't understand this.
The amount of your monthly check is based on your average earnings during your best 35 years. This is calculated and then converted to present value. Then a formula, which is quite progressive is used to determine the amount of your check. This is called the PIA.
https://www.ssa.gov/oact/cola/piaformula.html
For a relatively low wage earner whose lifetime average earnings are $2000 a month, their monthly benefit is $1136 per month. That represents about 57% of their average earnings. A pretty good return for a 6.2% payroll deduction. Not bad even if you consider the 6.2% employer match.
For a mid range earner, averaging twice that, or $4,000 a month, the monthly benefit would be $1776 a month. That's about 44% of their average earnings. Not as good, but still pretty decent.
Now, double those average earnings to $8000. Now the benefit is $2147 a month. That's only about 27% of average earnings. So a relatively well off does not get such a good return on their investment. They are in fact subsidizing lower wage earners.
This is a lot of the reason why they want to privatize it.