> "why exactly are they showing up at a donors gathering?"
Yes, this probably means the problem is even bigger than the sample demonstrates. Most of the people in uncomfortable retirement are not going to show up at all.
I wouldn't be that inclined to make assumptions about what sort of selection bias there was. I could also argue that people who show up at such gatherings are more likely to be people with time on their hands or who are making a concerted effort to network, while those who are working full-time are busier.
Of the MIT/Stanford software engineers I have known a long time and know what's become of them: one (60-ish now) had a fairly lucrative late career segment doing web search at Yahoo and is now retired; one (same age) is still working, doing Big Data consulting; one (late 50s) was in a two-career couple with two or three kids and is now retired; another (mid 50s) made enough in the stock market and miscellaneous other ventures to semi-retire, though he still does a little consulting; another (56) is happily in business for himself selling iOS apps; and I (57) am still working as a tech lead for HP Fortify.
I think the lesson is, if you're careful with your money in your 30s and 40s, you won't necessarily have to work into your 50s if you don't want to. Alternatively, take good care of yourself and keep learning new stuff, and you can be productive well into your 50s and beyond. But if you don't do either of those things, you may have a problem.
I'm in the same range and I would have to say that most of the people who pop to mind (caveat--there's probably some selection bias) have done pretty well.
Among people from school who I've kept in touch with. One founded a significant company. Another is Chief Scientist of a large IT vendor. (And another was--retired now--Chief Scientist at a large consumer goods company.) A few are consultants of various types. One is still a game designer (though he actually started that after school; he was a civil engineer).
I also work with a fair number of people in the same general age range. I'm sure some percentage are still primarily coding although a lot are development managers of various sorts.
Personally I worked and a Mechanical engineer for a few years but I've done technical marketing of various sorts or strategic/marketing advisory work for most of my year. (I do some programming but strictly on the side.)
An MIT bachelor's degree includes a decent amount of liberal arts. The HASS requirement has been around for a long time -- 1980s? http://web.mit.edu/hassreq/
I don't know when that particular name for it dates to, but some sort of liberal arts requirement has been around for even longer. To be sure, if you take the minimum and take courses that aren't really liberal arts (e.g. accounting or microeconomics), it's fairly minimal. But the opportunity is certainly there to get a fairly broad education.
Feynman writes about having to satisfy a liberal arts requirement in Surely You're Joking, Mr. Feynman, so the requirement goes back at least to the late thirties.
It's been a while since I read it, but I seem to recall his approach to it was what I assume to be the normal MIT student's: take the minimum he could get away with and complain about how useless it was.
I could be misremembering, though, and that was written much later in his life.
That's all well and good, but requirements are different from practice. In my understanding, engineering degrees and especially those from very technical institutions tend toward specialization. There also may be a factor in who chooses those institutions and how much they choose to specialize in both their education and career.
I honestly don't think there are many jobs an experienced MIT engineer couldn't do that a liberal arts graduate could. I think the matter here is most old folks with an MIT degree with a comfortable financial position would rather be unemployed just managing investments and other activities than work a low paying job.
That being said, he didn't exactly say what sort of engineers these folks were. Electrical? Software? Big difference..
Also, one thing that didn't jive, if they are in financially uncomfortable retirement, why exactly are they showing up at a donors gathering?