I am not a native English speaker and in some cases particular phrasing can sound neutral to me but actually be rude and vice versa. I always thought that "think again" in phrases like "If you think that ..., then think again" is something if not rude but at least passive aggressive. But recently I've encountered a lot of examples of "think again" that put my "this-is-rude" hypothesis in question.
For instance:
If you think the influencer’s penchant for big lips reflects a modern beauty fad, then think again.
or
But if the song sets you up to expect some kind of concerted attempt at a pop crossover — his John Legend moment, let’s say — then think again.
So, my question is - how much "then think again" is neutral? Can I, for instance, use it in corporate communications?