Sadly, yes, doing nothing in retirement is rarely a good thing.
As I approached retirement quite a few people warned me about making sure I have something to do (and surfing the interweb doesn't count as something to do). I also paid attention to others I know that retired and took on too much (one friend talked about how he was much much busier than he was when working).
So I will be working forever because I have an expensive hobby. However, I will be taking signals from some of my aviation friends who are retired.
One is a former KC-135 and 767 captain who retired from the airlines at age 60 with a United Airlines and Military pension. Oh and his wife has a government pension as a former ATC Tower controller. He is the youngest 71-year old I’ve ever met. He flies a Harvard and a Chipmunk, does formation training and Warbird checkouts, and last year had a knee replaced and a shoulder repaired. He was on the 1969 Ohio State National Championship team, but when he went to his 50th team reunion in Columbus this fall, he was taken back by how “old” some of the guys were. He refuses to let the”old guy” into his life.
Another guy sold his auto repair business to his sons, and also had a career as an LEO. His retirement business is selling radios to Police departments, and he restored a Hughes TH-55 Osage Vietnam era training helicopter. First flight should be in January or February. I think he’s in his mid-60’s.
That’s how I want to “retire.”