When a vaccine guarantees a near perfect sterility rating that is a culling for sure. It is a soft culling of the masses. In a single generation most of Humanity as we know it will literally die off with virtually no hope to ever reproduce again.

Aside from the vaccine caused mass sterility... just how will this adversely affect Humanity as a species? Mass rapes, sexual assaults, and worse will almost instantly become a much beloved daily activity for quite alot of people out there. Rape is just one of those things that you can be still be held accountable for child support. When you no longer have to worry about getting the woman or women you rape as a man and verse visa all inhibitions will melt away faster than an ice cube in boiling water.

This will be so much worse when people realize there is pretty much no next generation of humans. So what reason or reasons would you bother trying to remain a good or better possible role model for the children when there are effectively no more children to be a role model for? So yes a mass sterility problem in Humanity will very quickly bring the absolute worst elements in Humanity for the foreseeable future.