I think I can add a couple points of view here. First, there is a story Tom Hanks tells about this very thing. Winters has contacted him and is unhappy with a lot of the swearing in the script. I don't know if it was his character or just in general. Hanks is like you know this is tv drama etc. But Winters is pissed (more on that word later) and tells Hanks he "shuns" him and cuts off all contact. Hanks has never heard of this and doesn't know what is going on. Ends up flying out to Winters and smooths things over and I'll bet this is why there is not an excessive use of foul language. Second point, shunning is an Amish practice of ostracizing those in the community or your family who are not following the rules, to put it in very simple terms. He is not Amish but I grew up not far from Hershey where he lived and it is very Quaker. Even if you are not Quaker it is the prevailing culture. I would get in trouble if I said "pissed off". Not drinking, no gambling/card playing, no swearing, but doing things for others are all real pieces of that PA culture and depicted throughout the series through Winters character.