Just for those unaware - the social security pay-in is a percentage of your income, but the maximum amount of your income subject to social security withholding is capped at a fixed level that increases annually. The last time I looked, the cutoff was somewhere around $138k. So if your cumulative income for the year hits $138k in, say, June, you are no longer subject to SS withholding and your weekly paycheck goes up by a couple of hundred dollars or so as a result. Most people don’t hit this amount, but enough do that were the cap eliminated, it would increase solvency and possibly allow for an increase in payouts.
On the flip side, your payout from social security is proportional to what your pay in was. It’s still capped, and it’s not really enough to live on. Those who hit the cap typically have multiple other sources of savings for retirement and could easily contribute more to the national program.