My father is 64 and although he's had an era of poor health a few years ago (since recovered) he has no interest in retiring (he's a highly sought after executive consultant in his field).
He's probably the first generation to actually question the whole notion of stopping work at 65 and quietly going off to die. Like most of us on HN, he is able to work in a career he enjoys that isn't labor intensive (thus capable for older people)
The WorldBank says the average life expectancy in USA is 78 (http://data.worldbank.org/indicator/SP.DYN.LE00.IN?cid=GPD_1...) so if you finally gave up work at 73 that's only an average of 5 years you need to live without an income - and that for most successful professional workers this is probably manageable through savings and/or reverse mortgage on a reasonable sized house.
The pension industry hasn't really changed in 50 years yet the way we live, work, and end our lives has changed (and continues to change rapidly). If the shift is towards us working longer that means we need them less, so there is no reason for them to adapt.