I don’t believe it to be a sign of disrespect or lack of emunah to seek the reasons why, rather than accept a because I said so answer.
No, of course not, ???? ??? ????? ??? ?????.
Of course, l’maaseh we accept a “because I said so” answer, but not derech limud.
I think LF is right that the gezeirah is on the people of (iow people who dwell in) chu”l rather than on the place (see ???? ???? ?”?). Query why that is so; as I recall, they were concerned that upon return, they will continue to keep one day, but I don’t remember where I saw that.
Interesting question re: Simchas Torah. I’ll bl”n try to look around and try to find something. Perhaps I’ll be able to atone for my unwarranted insult (sorry again).