Assuming we're talking about women, that would be a little silly when in most cases the anatomy is different.

But honestly - I'm not trying to say all women need to try anal sex - but whatever opens some minds about it is kind of a good thing. I get really fucking sick of how when we're talking about m/m sex, anal is supposedly a given and almost no one is grossed out, but as soon as we get into the idea of women enjoying it everyone is all "Eww but poop goes there, nuh-uh!"