But lets take what you said as fact - the conflicting factor even here is that humans have a layer over the top of our biological programming, which results in people going against their "basic" interests quite often.
Not everyone does, but many do, and we are talking about humans on that layer - whether that goes against our instincts or not.
You are right the human factor is relevant and people can go against their "basic" interests, but statistics from census data and dating sites shows quite grim numbers. Wealth (as a proxy for social status and power) is the single biggest dominating factor for men with a very sharp drop at the bottom, and appearance (as a proxy for genetics) is the single biggest dominating factor for women. It also correlated to the size of peoples social support network, stress levels, overall health, and life expectancy.
Just looking at life expectancy, wealth for men has a correlation of about 10-15 years difference. Exercise in comparison seems to only have a correlation of around 7 years difference.
Absolutely fascinating question, I would not be surprised by this possibility at all. It seems quite probable.