This is indeed a fun way to illustrate Bayesian thinking! But I have a monkey wrench! There exist people who view smileys as almost explicitly connoting passive-aggression or sarcasm. Like the whole reason to add a smiley is to soften something mean. I’m not quite sure if there are enough such people to worry about but I think that that perception of smileys is out there.
Huh, that’s interesting. I wouldn’t have thought of that but now that you mention it, I also feel like that sort of perception can happen. However, I also get the sense that when you’re in such a situation, you’d be able to tell, and thus avoid having your smiley face misinterpreted.