I'm a bit beyond middle age, but in looking back have been a nudist at least at heart since I was preteen. Grew up with open locker rooms and nude swim classes as late as college in 1970, and longed for places to be nude. Unfortunately, society and possibly the norms of the family kept me covered except on rare occasions until I was in my early 40's. I'm still not a social nudist, but spend a lot more of my private time without clothing than at any time before. When home alone, I am nude most of the time. With my wife home, not as much, but certainly with less covering than if I were out.
I just turned 40 and personally believe I have gotten to a point that I want to not care what other people think anymore. Growing up there are so much expectations so you tend to be in line with social norms. Then at 40 you should be all set, right? Well that expectation stars to fade as you approach 40 and you look to older males for examples. And ( clothed or not) older men tend to not care what other people think and just live there life. So that is when nudism become a well why the hell not kind of thing. On the other side women have even more expectations on how they act and how they look. So they have even more layers to go against then men. So I am always in awe of women nudists ( young and old) that have found a way to ignore those expectations and be themselves. In writing this I realize that I want to know more people that can live their life free from those rules. Like I said great topic and these are just my thoughts.
Personally, I always wanted to be a nudist but I was body shamed as a teenager and was ashamed of my body/penis. It wasn't until I was in my late 40's that I found the courage to toss off my clothing and risk the taunts and laughter. Guess what? There were no taunts however I did get teased a little about my shyness. When I first came out of the bisexual closet and nudist closet it took quite a lot of beer to overcome the shyness. That's no longer necessary. I've discovered it's not about cocks or perfect bodies. It's about freedom and self acceptance.
Perhaps it is because we have the chance to retire, or not have to work so many hours, or the fact that we are totally comfortable with ourselves and are finally in a position where our private life cannot cause problems with our job.