for the next 20 years. we need to skip a generation. then let, by lottery, 10% have ONE kid. there's 10x more people on the Earth than can have a decent life. One man can impregnate 100 women, so sterilizing men is a waste of time and money. ALL problems are worsened (a LOT) by having too many people. this is a way to help almost everything, and nobody is hurt by it. there's nohing special about anybody's genes. I got a vasectomy decades ago and should have done so at age 18. I'd have scored a lot more pyssy if I had. 
I have had no kids never wanted any of my own. I've adopted one, tho.
I have had no kids never wanted any of my own. I've adopted one, tho.