Funny how there aren't any article telling the rich to get to work or risk dying.
I think that this is the key point, and I'm happy to see this level of insight coming from relatively low-count posters we haven't heard from much. Please, contribute more!
Yes, the correlation between working longer and living longer needs to be carefully evaluated for causation. I would argue that people who aren't healthy enough to work can't delay retirement, not that people who do delay retirement are healthier, even though those to things generate the same correlation. I also think it's important to look at exactly what age range we're talking about here. I suspect the age/health correlation is based on observations of people 60-65 years old, and doesn't include a representative sampling of 35 year old retirees.
But as Moustachienne pointed out, there does appear to be a visible undercurrent of classism involved in these sorts of pieces. Remember that we've always had a rentier class, people who were born financially independent for various reasons, and no one has ever encouraged them to go become bricklayers or secretaries so that they can be healthier. They are assumed to be able to pursue their own self interest without the need to be bossed around by someone. Since when is servitude a requirement for happiness and health?
I agree that it's good to find purpose in your life, to find a way to stay busy and engaged so that you don't become an alcoholic or a hermit. Historically, the rentier class has solved the problem with fancy social obligations like charity balls, or overseeing the growth of their regal estates with gardens and fountains and stables and such. They may have massaged
noblesse oblige to include things that personally benefited them, like supporting artists and musicians, but they still held onto some kernel of responsibility for their communities.
Retaining that position of power, however, requires that most of the people in that community are not financially independent. They still need bricklayers and secretaries, and gardeners and stable hands, to keep the community running smoothly. Like any privileged class, they had strong incentive to prevent too many people from abandoning those economically productive jobs to live off of the profits of others, and so I would expect articles like this "3 reasons you shouldn't retire" one to be a pretty common sentiment from that class. "Don't save! Don't invest! Don't be like me! I need servants!"
Money is a tool, right? It's just an arbitrary accounting system, not a real thing, but it confers real control because it allows you to direct the work of other people to your benefit. Mow my lawn, repair my mansion, cook me dinner, wash my feet. I will transfer imaginary units of value to you if you do real work for me in the here and now. Never mind where or how I got those imaginary units of value (but I certainly didn't work for them), all that matters is that I claim to have many of them due to my social status and that you desperately need more of them because of yours. Sounds pretty fucked up, right?