American culture, including Puritanism, being exported worldwide since the 1980s, first through Hollywood and then through tech.
You will not find a less Puritanical view of the matter on a forum composed of mostly people from the US or deeply embedded within its culture, like many software engineers are.
For US and tech, sex talk and sexual freedom is a concept best avoided. You'll find more people arguing against gun control than arguing in favour of sex work or that age of consent is an arbitrary, cultural limit, not a hard one.
EPFL being an scientific organisation with international reach is influenced by this US cultural effect, and in general Switzerland is culturally more prude than its neighbours.