There are some gems in the rough though. If this genre of video interests you, definitely check out the USCSB (U.S. Chemical Safety and Hazard Investigation Board) channel.
Youtube is definitely developing a subculture of channels that essentially copy existing work and put them in video form. I guess they are generating bespoke content - There's a fair bit of effort that goes into creating an engaging and cohesive video. But the fact that most of them do not properly acknowledge sources leaves a bad taste in my mouth.
Don't be, there's a lot of art in the presentation style. This particular channel puts a lot of effort into being very respectful and presenting a certain tone and speech register which I find rather charming. Of course not all channels do add this kind of value, but just ignore the ones that don't! :)