It's very late and I'm obviously rather tired because I've started my usual practice of noticing odd things. While watching the Chief Exec of Tesla Cars explaining the attributes of their new autopilot hardware and software, I noticed that after he'd finished explaining every point he reaffirmed his message with a few nods of the head. Now I've seen quite a few Americans do this over the years, but the first time I noticed it was on The Muppet Show when Kermit the Frog used to nod in the same way after every announcement. The Chief-Exec reminded me of all this. Which leads me to conclude that I've found an US English gesture that doesn't happen on this side of the pond, or anywhere else for that matter, and that it's time I went up that wooden hill [to employ a well used UK English saying] before I start noticing anything else odd.
And NO, don't say it's because all Americans are Muppets.