There have been a number of studies done about retirement killing you more quickly. From several countries, and several different universities/research places. I retired several years ago, and before I retired I read several of these studies, which all came to the same conclusion. The hypothesis was that people needed work to give meaning to their life. I figured that I had penty of hobbies to give meaning to my life, and I wouldn't be one of those statistics.
At the time a new study came out, looking at retirees in France (from the state run electrical company?). This had been done using health records from some enormous number of people (17,000?) from a few years before they retired to about 10(?) years after they retired. The graphs actually showed that on average people gained five years of health in the first two (?) years after they left work. Note: all this is my memory of this study.
I think that if your live has value and meaning to you, ER is a very good thing. From personal experience, the change in quality of life is immense! Maybe I had it worse than others, but my workplace was very confrontational, and though I always enjoyed the work, the stress made me a bad person. This has changed so much since ER!
There has always been a group of ER people around - they were once the aristocracy, and many of the clergy, who had land holdings that paid them to do whatever they liked - usually not much of anything. Unfortunately, in the 100 years since retirement was invented for ordinary people, it has been synonymous to being "useless" rather than highly thought of with everyone doffing hats at you. I think many of the studies show poor outcomes because of this definition rather than an inherent flaw with ER.