People who enjoy exercise are in the minority. Literally doing anything I find interesting would be preferable to exercise, I exercise because I have to, not because it is enjoyable in any way.

It's the "forcing yourself to do something unpleasant" part which improves mental state, not the fitness itself. I suspect that people who find exercise enjoyable, or are forced to do it, don't get the same benefits.

This article is basically just the marshmallow test: https://en.wikipedia.org/wiki/Stanford_marshmallow_experimen...

And 4-6 hours a week would be a low week for me =)

Agreed, cardio is actually generally enjoyable, hence the massive popularity of run clubs and marathons. It is unpleasant for the first couple months of someone 20 years sedentary and overweight going into 9/10 effort runs though (when they should jog)