For the record, I think this is a stupid argument on both sides. Arguing about what God would or would not have done is like arguing what would have happened if Soap had lasted another season. It requires us to know not just God's capabilities, but also his plans. And one can always argue that he planned for us to be shambling wrecks who die of sorts of things because, well, because he has his reasons.
That being said, the male prostate is pretty poorly designed. It forms a donut around the urethra. If anything goes wrong with it (when something goes wrong with it), it impacts the whole urinary system. It really only makes sense so long as we're built to die before it has a chance to malfunction.