Hello, I agree with bms42 : I had the same reaction and see arguments for not distinguishing emotional safety and aesthetics.
Maybe you could add the precision your post adds : if the NPC does something I can’t stand, the game stops. That may be just the chronological order of presentation. As is, it’s like you want the reader to infere as if from a book of law : that is not robust to my reading. And safety needs robust and redundancy.
Or is it what you mean, that the game should then stop ? and who would call it stop ? the player unable to stand the fictitious scene or the douche GM ? In my opinion the rule most of all lacks a clear handle. Read “everyone must like what is played” at the beginning of the rule. It sometimes look as if you wanted to disclaim responsibility.
Maybe to prevent safety AND safety rules abuse you need two short rules instead of a big curved one ?
I don’t know.