If I'm reading this right, you're under the impression that a condom protects you against the vast majority of STIs, correct?
Yeah no. Condoms are primarily preventative towards towards diseases that are spread via Semen, vaginal fluids, and skin to skin contact only on the area it covers. Syphilis, Herpes( which can also be spread via oral sex ), Genital Warts, and crabs as a loose example ( There's more ) are not prevented by a condom. Aside from HIV/Aids ( in which case African American women are the highest rate of infected ) that quip was pointless as was this post.
Odds are, if you have medical insurance, you can get a vasectomy for a co-pay of $20 and the procedure only takes about 15 minutes.
I'm fairly sure that Planned Parenthood in the US also does it cheaply.
My gut tells me that the guys who are responsible enough to get vasectomies if they really don't want kids are also responsible enough to wear condoms. The converse is likely also true!
If you roll out a treatment that is just as effective as a vasectomy, but is 100% reversible, and a whole new class of men will enter into the picture: men who aren't yet ready for fatherhood, but who want to be fathers someday. Many of them will not be in monogamous relationships. Some of them will not consider the risks of STDs as rationally as they considered the risks of pregnancy.