From my observation it would seem strong reactions to life events is intrinsic to Korean culture. For eg, if you watch Korean news for any period of time and see how they react to everything from tragedy or just protesting about something they feel is important, it's always with a lot of deep passion, which can appear as overreaction to someone who is from a more subdued culture.
When it comes to tragedy, I don't think there is any right or wrong way to react, but I definitely see a stark difference to how Koreans mourn and how many people in the west mourn. In Korea there seems to be a lot of wailing, bawling and flailing about and sometimes even violence toward the person or persons they feel is/are responsible. Of course, you see the same in the West too, but on a much less amplified scale, imo. In any case, I certainly think it's an interesting cultural phenomenon, though I can hardly find it believable when I see it in dramas.
