“Are there any circumstances where western sensibilites might change a halacha”
Certainly Though with DY’s caveat “It depends what you mean by “change the halacha”.”
to add to his List
showering on yom tov is likely shava lechoil nefesh today and possibly allowed (though gezeiros habalanimis a seperate issue :
on the other hand many say smoking is no longer shava lehol nefesh and is thus assur on Y”T
Rabbeinu Gershom’s cherem was liekly done due to “western sensibilities” arguably “changing halacha”