there are so many genetic diseases out there. Baldness affects a lot of people. Depends if you look at age 20 or age 30.
then you have the recessive genes. You get rid of 70% of the population that has a condition, then you let the other 30% with recessive genes bread, and then their kids have more conditions.
with huge populations, it may not be a bad idea. But look at guys like Jayman, good muscle genetics, 9.5 on hotornot.com, but balding. Should he be sterilized. Sometimes you got to take the good with the bad.
oh, and how about sterilizing every guy with a dick less than 6.5 inches. That should reduce the remaining guys buy 80%. Then the few remaining guys can impregnate more women, if those women don't have the genes too. But watch out for inbreading!