Birth control for women can have really major side effects that it wouldn't even make sense to be on in hindsight. Also, I've known women who got pregnant while on BC, so nothing is 100% proof. The morning after pill (Plan B) isn't something that should be taken regularly. It is intended to be used only in the case of "emergencies"- when unprotected sex was had or condom error, etc.
I do know there are other forms of BC for women, but I'm not very familiar with them. If there's a cheap one with hardly any side effects, please enlighten me. A condom seems like the easiest option. It's cheap, barely any side effects, and you're protecting against pregnancy and STDs. What more is there to ask for?
Also, in terms of whether or not men should be held accountable for impregnating a woman but not wanting the child, obviously the ideal is for both parties to come to a decision together. Though I do agree consent to sex and consent to pregnancy are two different things, because there is this "blurred line" (the child growing inside a woman's body and not a man's) those not looking for any babies should be aware of the risks and take all necessary precautions.
I don't think fair is always equal. Men and women aren't "exactly alike" in this specific case, so it's illogical to treat the situation as a matter of equality. It's a fair decision because the fact of the matter is is that it's not your body, and therefore you can't dictate what ought to be done.
It would be too complicated for the government to mandate laws in which men can waive off responsibilities. As adults the implication is that people shouldn't be passive in regards to sex and yes it sucks that one mistake can cost you, but this is with anything in life. If you're unsure if your partner is on the same page as you then your best bet is to find another partner who is.
This seems like just basic relationship skills in general.
Edit: Neither parent should be able to waive responsibility unless the other consents to it. I mean
we talk a lot about women "trapping men" but I've read/heard of stories where one guy has many kids for many different women. I mean
there comes a time where people should be held accountable for their actions, having a child is one of them. Tough shit. It's not the child's fault, and if you're the parent you should be the parent.