That would not be a counter argument, as OP seems to labor on the simplified assumption that sexual desire has evolved to ensure procreation, and then it doesn't really matter if you intend to father offspring or just to fulfill that desire.
But it's not that easy, because sexual desire in Humans (and many animal species) is way more complicated than ensuring conception.
And more importantly, rape is more complicated than sexual desire. It often isn't about the sex. And I agree that the referring to biological urges when talking about rape is somehow releasing the perpetrator of some of the guilt. It is always also a lack of judgement, empathy, self control and so on. Nothing except very rare brain disorders can make someone a rapist unless he chooses to be.
But it's not that easy, because sexual desire in Humans (and many animal species) is way more complicated than ensuring conception.
And more importantly, rape is more complicated than sexual desire. It often isn't about the sex. And I agree that the referring to biological urges when talking about rape is somehow releasing the perpetrator of some of the guilt. It is always also a lack of judgement, empathy, self control and so on. Nothing except very rare brain disorders can make someone a rapist unless he chooses to be.