The nudity is not gratuitous or exploitative, though. The point of that scene was to show how the mechanised form of reproduction replaces the covenant of marital union, by transposing the usual method of penetration. This is not about conservative morality like Friday the 13th, where young people get punished for having pre-marital sex or engaging in other illicit behaviour. They are a married couple fulfilling their duty to 'be fruitful and multiply' (Genesis 9:7).