If he said it "kills the battery" would you say that it trivializes actual, no-kidding murder? I doubt it.

Also, men can get raped too. I don't just mean women raping men; men rape men too. (Would a "Don't drop the soap" joke be too inappropriate here?) It could be argued that assuming only women can be raped is the misogynistic position.

Last, saying that we've got to cut this out "if we want a world with less rape in it" is, frankly, ridiculous. Nobody is going to read the "battery rape" comment and subsequently be more likely to rape someone.