It will be like a bank run, all those eligible who are not yet taking benefits will immediately begin taking benefits and the whole think will collapse.
I have been getting my SS ever since I was deemed ‘eligible’ for full benefits, at 66 1/3 years. Now 68+.
Still working, so I don’t ‘need’ the money yet.
Have been putting the money in the bank and an IRA ever since.
So when I do retire finally at 70, I’ll have a fairly good retirement, house paid off in 2017, SS plus a small VA pension..................
They are not going to cut the benefits and the program will not collapse. Not quite.
Natural mortality and inflation will take care of their problems. And if the monthly benefit payment might be enough to pay for a lunch or a few days of canned cat food? The seniors can eat bugs and be happy. Or not. Their angry votes won't mean anything to the politicians in an era of ballot harvesting and standardized election fraud. And the seniors don't have any money left for campaign contributions, so fuck 'em.
But the monthly benefit payments will keep coming, as regular as the sunrise. Probably even after the beneficiary has died. They need to keep the younger folks calm with the illusion they might get something. (Spoiler - they won't)
The Millennials, and the X-ers (people now in their 40s and 50s) are going be stuck with the problem of fixing this. It will be an ugly transition. And the karma from that transition will be a cold-hearted bitch when they reach their 70's. If they reach their 70's.