My wife is retired at age 63. She can earn up to 15,480 per year without her benefits being reduced. After that amount her benefit is reduced by 1 dollar for every 2 dollars over that amount. I still work and will as long as my back allows me to get out of bed which has no effect on her retirement at all. SS follows the individual.
I know this because she quickly tired of being unemployed. So she got herself a job at the local casino doing retail which she enjoys immensely. The pay isn’t much compared to her income as an accountant but she loves it.
The distinction that needs to always be made is between “reducing benefits” and “causing SS to be taxable”. Causing it to be taxable at some level is pretty much a given. Married filing jointly and household income over 32k begins to cause SS benefits to be taxable. There is a complicated calculation to determine what percentage of the benefit is taxable. The benefit isn’t reduced, but obammy gets to tax part of it.