How about scrollaway's law of post quality: if your sarcastic post sounds believable enough for Poe's law, it's a shitty post no matter how it's interpreted.
Sarcasm's law: without a tell, it doesn't always come across as sarcasm without common sense. The latter is often missing these days, hence Poe's law.
internet's law: The average level of common sense, intelligence, sense of humor, benefit-of-the-doubt, and decency decays over time.
airhead's law: Quality sarcasm poetically-highlights an insight rather than ejaculates (meaning no. 2) a humorous quip.