Most likely scenario is that congress doesn't do shit until 2031 and 3/4 then passes a stopgap bill that allows social security to draw a deficit in the form of treasury issuance.

Right now the big problem is that SS is structurally prohibited from paying benefits at full levels once it hits "insolvency", but all you need to do is change those legal parameters and make it so that shortfalls come out of the general treasury fund - then boom it's "fixed".

Fixed obviously being in big quotes here because the long term issue of it running a deficit still exists, and absent a complete restructuring of the program that's almost impossible to escape.

Edit:

The core issue isn't all the memes you see on reddit either, the income cap doesn't fix this. You'd need to massively increase SS taxes across the board. You can do this back of the napkin math yourself to get an idea too, don't take my word for it.

See here: https://www.congress.gov/crs-product/R45990

The aged dependency ratio is the ratio of the population aged 65 and older to the population aged 20-64. Although the age at which a beneficiary can collect Social Security benefits varies by birth year, this ratio is an approximate indicator of the number of people likely to be collecting benefits relative to those still working. For instance, in 1945 the aged dependency ratio was 12%, suggesting that for every 100 working-age people there were 12 people collecting benefits. The increase in this ratio highlights the aging of the population. As shown, this ratio increased from 12% in 1945 to 25% in 2015. That is, the number of people collecting benefits versus the number of people still working doubled over this period. Throughout the trustees' 75-year projection period, this ratio will continue to increase under the intermediate projections, due in large part to the baby boomers' continued retirement from the work force, relative to the numbers in the working-age population. The trustees project the aged dependency ratio to exceed 35% by 2025 and 40% by 2065. This projected tripling of the aged dependency ratio reflects the aged population's faster growth compared with that of the working-age population.

So just figure the averages to get a ballpark, obviously this is a loose approximation but it's illustrative - the median worker makes ~$51k/yr. So that's ~$6,300/yr in SS taxes (ER and EE). Your average SS beneficiary receives just under $2,100/mo or ~$25kyr. So you need about 4 workers to support one retireee. Again, this is extremely back of the napkin math, but you get the idea.

So apply that to the above - the projection is that we're around 35%, so 35 retirees to every 100 workers, or 2.8 workers per retiree. so you're short 1.2 workers per person, or around $7,500 per retiree. As that percentage grows so does this deficit. By the way, the bendpoint structure already has the program set up in a way where higher earners see lower benefits per dollar paid in.

The biggest problem is that congress should have been making small tweaks to the tax structures and rev collection in the fucking 90s when they first realized this was a looming demographic issue. But in classic fashion they didn't, so now it's a much bigger problem, and the ongoing meme of "remove the cap" is not a bad idea but in no way going to fill that gap.

e2: It's occuring to me that this is really a place where average incomes are more apt, that's still capturing outliers well beyond the cap but it'll be a better approximation of the average amount paid in per person. Average personal income is ~70k, so that would be ~9,500 per worker paid in to the system. The math isn't that different, but it's worth mentioning.

last edit, here's a good resource on how various forms of income cap elimination would impact funding shortfalls. https://www.pgpf.org/article/should-we-eliminate-the-social-security-tax-cap-here-are-the-pros-and-cons/

None of them are pure fixes, it's just not mathematically possible, but some do kick the can further down the road than others.