I've heard this is more due to the US's religious 'puritan' roots. Back in the 70s, as an example, Canadian broadcast TV used to censor violence quite a bit,

I've heard this is more due to the US's religious 'puritan' roots. Back in the 70s, as an example, Canadian broadcast TV used to censor violence quite a bit, yet not nudity as much. The US was the reverse, with violence on OTA TV more freely shown, compared to nudity. Canadian vs US broadcast cuts of some movies had to be unique as a result, or US cuts only shown late at night. I imagine the same logic may apply to "swearing", from a religious viewpoint. When I was young, we used to joke that Canadians censor violent death, and Americans censor love...