It is SOMETIMES legal, which means that it is in the other times illegal.

Not necessarily that either. You’ll only possibly receive a charge if your conduct was intentionally misleading with purpose to harm. Yelling “fire” in a theater while in a Gen Z crowd (“this is fire”) or while listening to Metallica (“Fight fire with fire”) isn’t going to get a charge either, even if it possibly causes a stampede. The crime therefore could be accomplished with far more alternative words than just “fire.”

The point is: Legal experts unanimously agree this analogy is terrible and should never be used. The Supreme Court also thought so, completely overturning the case it originated from just several years later.