Earlier quoted context omitted.
You need only look at the rampant abuse of Content ID to see what the likely result will be... "Sorry, the video you uploaded 'Me playing Beethoven on the piano' contains BEETHOVEN'S 5TH SYMPHONY by BMG-EMI-XYZ Music Corp. You cannot upload this video."
Is that illegal though (wrongly blocking a video)? If it isn’t, YT can just shrug it off.
Measures like this only serve Big Content. And badly, in my opinion.