The NW video was very revealing and confirms some suspicions that I've had.
From my own experience, during an RV-7A landing, I experience a significant shimmy event, which I believe was initially caused by low nosefork breakout force. There was a pretty good gusting crosswind from the right that day and immediately after de-rotation/NW touchdown, there was a significant vibration from the nose gear. Fortunately with those winds, the ground speed was quite low at de-rotation and the event didn't last long. It was later found that the breakout force had creeped to a lower than standard value probably due to wearing of the Belville washers.
On another occasion, while formation landing in trail, I watched the same type of event occur on an RV-6A directly in front of me. Since we are usually quite close (<300-500'), it was quite easy to see the nosewheel fairing swinging back and forth in the breeze on this aircraft while the pilot dealt with a left crosswind, power changes, and associated turbulence from aircraft directly in front of them. Normal stuff if you are used to doing formation arrivals... In the flare as the pilot pulled the power to idle, the nosewheel cocked to more align with the crosswind. Then at de-rotation/touchdown it was quite evident that the nosewheel acted like an unbalanced shopping cart wheel and vigorously vibrated for 3-5 seconds as it dissipated energy trying to align itself with the opposing forces of crosswind, runway, and prop blast. I later asked the pilot if they had a nosewheel shimmy event, to which they replied to surprised, "Why Yes, how did you know..?"
Clearly the breakout force was not set high enough...
And yes, nose, main, and tailwheels do spin in flight, although not as fast as you might guess. If you even are in formation, especially Close Trail looking up at a tailwheel, you will notice that some (with good bearings) spin slowly in flight. Nosewheels also do spin sometimes depending on the model and torque setting used by the builder. I'm guessing that this is not a factor as the rotation is generally quite slow.