I have a Model 3 2021 Performance (since Jan 31) which also has the same sound/vibration from the video. It is definitely related to HVAC, but possibly not specifically AC (heat pump). I know this because (a) it happens even if stopped and/or in Park; (b) it does not happen when the AC system is switched fully off; (c) it happens if the AC (ie. heat pump) is off, but the fan is still switched on. I tested the cases long enough to know that it's thus definitely connected to HVAC. However... note that the HVAC system is also used to run other heating/cooling, eg. the battery, so the things we switch on can be different to what is operating. In my case it does not happen every drive, even though the fan is always on for some ventilation. When I thoroughly tested these cases, the outside temp was about 20C (68F), and the car had been calmly driven a short distance, so there was no chance the battery needed cooling (or warming, I assume).
It's quiet enough not to be annoying, but loud enough to be strange. Regardless of ICE vs EV, there is zero chance any of my other cars' HVAC systems produced a similar sound/vibration. I know sound=vibration, but this one is unusual, in that it is just significant enough to feel rather than just hear. I also know that unforeseen vibration can lead to premature failures, so I am hoping that whatever it is has an intended purpose rather than a design oversight. If I had to guess at a physical description of the source, I would guess either: a variable speed fan where blades or duct shudders briefly as the fan passes through a natural frequency; or something driven by a toothed belt where the system passes through a certain speed or load and the belt shudders briefly as it passes through a natural frequency.