There are so many things to question, even the basics: history.stackexchange.com/questions/9456/…

But also the huge influx of non-puritanical immigrants when the country's culture was actually formed

it's almost as if John Winthrop is personally responsible for how the USA and Canada deal with sexuality... And that in the entire European continent no puritanical thoughts were the norm except for these small few that founded these United States (what is referred to as en.wikipedia.org/wiki/Victorian_morality).

All these assumptions - and those in the OP - deserve to be questioned. There are like 24 Skeptics questions in there... each has their own full subfield of cultural research..... How can you truly stand by your answer - even in the most abstract form - in that light? Are you not persisting a myth?

Do you trust that the experts on this sub-site can accurately evaluate the correctness of your answer? Based on their expertise of human sexuality - I mean.