That is very good observation :)
I personally know men in their 50s and 60s and 70s who really boogie on the dance floor, they are very energetic, always. I have noticed that those men don't have problems. This didn't sound right... lol They are very open and outgoing, their personal live is perfect and all they do is enjoy life as it is.
Personally I think why men don't dance is because they have problems pile up over the years that's why they are stressing and dancing can keep them away from figuring our the problems, so what they do is think and socialize. :)