>> Aren't there diminishing returns with Social Security ? so at some cutoff you are NOT getting more regardless of how much more you work
Yes, Social Security is highly progressive. As I understand it, it takes your average monthly income over your 35 highest paying years, indexed for inflation, and pays you (2024 numbers) 90% of your monthly income up to $1,174, 32% of your monthly income from $1,175 to $7,078, and 15% of your monthly income above $7,078. There's also a cap on the Social Security tax and so a cap on the monthly income that is considered.
People refer to those as "bend points" in Social Security benefits, and there is a greatly reduced incentive to continue contributing to Social Security after reaching the second bend point. Someone who is 49 today likely started working as a teenager and would have close to 35 years of income credits (and so only a few "zero" years in the calculations). If they spent much time in a high paying job they would be close to or past the second bend point.
There is a maximum. It's also the case that your social security income is capped, too. I think that a person earning a million dollars a year for 35 years doesn't look any different to social security than someone earning 200k a year for 35 years, because both are well over the income cap.
I haven't read any of the FIRE stuff, but I wonder if it ignores social security. I'd argue that you can't say you're Financially Independent if your early retirement planning is dependent on social security; it's your money (...right), but there are rules around it, and those rules change.
In the long run we are all dead
> And Social Security in the US pays less the less you work.
Aren't there diminishing returns with Social Security ? so at some cutoff you are NOT getting more regardless of how much more you work