"Birth control" is ridiculously available. "Hormonal birth control" can have serious side effects and interactions, at least at the level of something like tylenol-fortified opiods or mild antidepressants, to say nothing of any net public-health effects (even after you account for "unwanted pregnancies"). Hell, testosterone, the direct analog, is Schedule III.

But some people have a political interest in promoting infertility, so quasi-OTC it goes.