As long as you can get a job , a salary , raise children (even if you dont even know what you re doing) and are able to fuck/satisfy your woman, everything else is "secondary". Survival for human beings only depends of these main factors. Humans also tend, have the capability, as ugly or stupid they are, to find someone who fits to themselves, selecting their fuckbuddies, ultimately to insure their survival by breeding descendants.
Now if you re "beta" "alpha", happy, depressed, it may affect your life and chances of survival/ seduce other people but if you can secure the basics you're set, period. Being smarter/more productive than other human beings (understanding the rules/the game better than they do) will only get you more money, a "better survival" than others, but point is, even the dumbest guy who can work a $8.50 an hour job can survive. He might be depressed all life long, but at least he can survive.
Now, if we were living in the stone age and physical capacities were still predominating, of course we d have to be smart and muscular.
Nowadays most men are into weight lifting for cosmetic purpose, just because they are muscular or "big" doesnt mean they re secure, happy, psychologically speaking. Even rich people can be unhappy. Takes a lot more than just "one ultimate" thing to be happy.
Anyone can survive whatever his shortcomings in our modern societies, let's see how long it will last.
Natural selection, survival of the fittest , smartest, are still at work, and aint gonna end anytime soon.