> Sexual competition is not nearly as simple as job competition, for several reasons.
I think you have an oversimplified view of the employment market.
> Many people have multiple sex partners, but a single job is staffed by a single person.
Employers often have many, many employees -- sometimes more employees at one time than anyone has sex partners in a decade.
> Sex isn't required to eat or keep a roof over your head.
. . . and working at IBM probably won't give you herpes.
> Sex isn't taxed.
Thank goodness.
> Sex doesn't go on your resume.
Not your professional employment resume, anyway -- unless you have sex professionally (as in the case of porn stars or Las Vegas prostitutes).
> Sex is between two people (or so), not a person and a corporate entity.
. . . and one doesn't normally fill out an application to get hired by one's spouse. So what?
> People don't involve lawyers or accountants before having sex.
. . . except sometimes. Have you heard of "white weddings" and "prenuptial agreements"?
> Trading sex for money is, in almost all parts of the US, illegal.
The porn industry is huge in the US. There's definitely some sex going on, there.
> Individual's choices leading to STDs or pregnancy don't compare, on a magnitude level, with governmental regulation changes that affect employment because the majority of Americans who have health insurance are only covered thru their employers
On the other hand, governmental regulation changes meant to address STDs do at least match that "magnitude".