I am from Czechia, which I guess globally is part of the West (shame on us) and I think popcorn as used here in this forum is definitely sometimes passively aggresive even when used by Westerners (shame on us).
However, I think this discussion assumes there are some fixed meanings to signs or language. The opposite is the case - signs have context-dependent meaning, and that is true especially for emojis, which are still new, fluid and rarely used. (I only know this emoji from here, so my understanding of it is OSM community specific.) Take an example of the heart - it can be used both to signal strong approval or affection, but when applie to an opponent, it can convey a high degree of derision too (i.e. “you are so beyond the pale I have only fake love for you or something”).
There is no single meaning to an emoji, one needs to know the whole context (i.e. who is speaking, what his or her intentions are, what is the setting of the communication etc.) to proper evaluate it and even then things can be open to interpretation and post-interpretation. While there might be tendencies in different cultures (or comunities inside of those cultures) to understand a given emoji in a certain way, to look for a clear-cut difference in meaning is futile, I am afraid.
P.S.: I think the adoption of that emoji is silly.