I'm not sure such an attitude is healthy or sustainable. We fought hard to get a 40 hour work week, why do we feel pressure to go back on that and work in our leisure time?
Personal development means more than sitting in front of a tv.
I want to need to work less so I can be productive for myself.
There are many hobbies where you don't produce or monetize anything, but they are still better watching TV. For example, playing a sport, learning an instrument, reading books, learning a new language, etc.
The distinction being whether you are producing something or learning something just for its own sake.