In the backstage videos of music videos, you can see that camera operators are filming with small video cameras.
In the backstage scenes of TV shows, you can see that cameramen are filming with large cameras that they carry on their shoulder (or mounted on a tripod).
Comparing the quality of music videos and recordings of various shows posted on YouTube by TV channels, I do not find any difference.
It seems that small video cameras shoot just as well as large video cameras.
What is the difference?
Furthermore, whatever company is doing the shoot will use their best camera for whichever project. If they have one of each, they’ll often have the smaller camera capturing the same events from a second angle, or getting behind-the-scenes footage. I’ve been that BTS guy holding the smaller camera. For BTS, the lightness of the smaller camera makes it easier to catch unexpected BTS content, if you have to swivel around or zoom in on the fly, for example. No one cares if BTS footage is shaky.
Personally I think the shakynes adds a lot to the BTS footage. It makes it really feel like BTS when the cameraman needs to spin around and move to capture something unexpected. Compared to “Oh something unexpected, just so happens to take place just in front of this conveniently placed camera, that is just on filming a random wall, how lucky”