I think that, for the benefit of DF, by default should not include some things yes, but it shouldn't exclude them from implementation either. And I'm talking about all the touchy things, feces, urine, slavery, rape, sex, drug abuse, prostitution and whatever makes you shiver (surprisingly, representation of senseless death and killing are accepted in our society even being something far worst).
I know is a rather hypocritical call, similar to Total War approach, where they don't include violent (as in realistic) effects to the battles in oder to have certain rating but then after a while they release the money-grab DLC with them anyway. This way they get to stay on the desired rating to boost sales (because somehow teens killing humans is okay as long as they don't see the blood, as if shooting someone is okay as long your close your eyes) and then please (and get revenue from) the older, bloodthirsty fans.
Of course not that Toady should care about stupid artificial and meaningless ratings that exist only to "comfort" the "worried" parents of today. But is understandable he want to keep the game image clean in order to attract a broader audience.
In the end he's making the game and it all comes down, as always, at what he's personally comfortable working with and what he thinks is better for the game.