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?
A few reasons, lenses are one, output options and durability are others. Many DSLRs and mirrorless cameras used for YouTube and low budget documentary don’t have the ability to output live video to a vision mixer or don’t do it in a way secure enough or high quality enough for live broadcast.