Because the benefits are capped. Why should the "wealthy" pay more and get less?  the benefit is capped based on the $118,500 income.  If the tax cap is lifted then the benefits should rise accordingly and not be capped.
We really should privatize the system, the government basically stole our money.  My children and I would have been way better off investing the money ourselves
At least with social security everyone pays SOMETHING, unlike our income tax system where 1/2 the people pay NOTHING