The taxes on SS payments go into the general fund, not SS fund. Tax cuts increase federal revenue.
Since LBJ the entire SS Trust Fund is placed in General Revenue. Which was and is a crime. The govt.spends money right out of General Revenue (including SS fund money which should not be there, and is in excess of total general revenue) and then borrows from the Federal Reserve Bank to make up the difference in money they should not have spent.
Then sends the “bill” for this credit borrowing right back to the taxpayers. Neat trick and absolute bullcrap. The Trust Fund should be left out of General Revenue, and also left alone (not borrowed against like some piggy bank they can raid).