YouTube Demonetizing "Meditation", "Stock Footage" & "White Noise" Channels

Recently, over a dozen meditation, ASMR, stock footage and white noise channels have had their entire channels demonetized for "duplication". 

What does "duplication" mean?  According to the YouTube Partner Program rules, duplication is not allowed. 

They classify "duplication" as
- Audiovisual works like TV shows and movies
- Sound recordings and musical compositions
- Visual and written works, including paintings, posters, articles and books
- Dramatic works such as plays and musicals
- Video games and computer software

Youtube channel demonetized for "duplication"