NC-17 Bah!
Let's be honest...
"Shame" got the dreaded, rare NC-17 rating for one reason alone!
Because it dared to show an unclothed penis, in slight excess, more than once.
Usually when it was shown, it wasn't even in a sexual manner. A man walking nude in his apartment then taking a piss is perhaps excessively flashy, but not sexual.
True, there were other moments showing penis that were sexual but also brief.
Why is it that cinema has been able to show fully nude females for decades yet if a penis is shown the MPPA barks?
I say good for Fassbender for taking on the challenge. He obviously has nothing to be ashamed of, but it still was a risky career move.