You're right that it's an almost impossibly high bar to clear, but saying that you can't be prosecuted for it or that it's not illegal is pretty darn misleading, or at least glossing over some pretty important nuance. It's literally the example the Supreme court chose to use as an example of one of the few times you CAN be prosecuted. Telling everyone the opposite isn't helpful.

As I said, I haven't watched Legal Eagles full video, but I don't like that ever since that video came out everyone on the internet tries to correct anyone who uses the phrase even in it's colloquial sense. Maybe the source video covers the nuance (I wouldn't know), but the folks on the internet "umm acshually"ing everyone seldom do.