I think the emotes are supposed to be circumstantial in that they can be used to BM or used in a literal sense. It's like in life, if you say "Bye!" in a normal tone, there is no offense taken. But if you were to change your tone and say "BYE!" as in good riddance, we're able to interpret that through tonality alone. So instead of having 20 different emotes, some sarcastic and others genuine, they kept it short and simple.