In 1998, the United States Congress passed a bill called the Digital Millennium Copyright Act (DMCA) that, in part, was designed to protect artists from having pirated copies of their works distributed and monetised online. At the time of the bill, and for the first time in history, creative works could be easily copied and distributed throughout the internet without proper payment to the author of those works, and the DMCA sought to protect the creative people whose livelihoods depended on getting paid for their work.
But the DMCA has a loophole.
It is called a “safe harbour provision” and is applicable to “Information Location Tools”. The clause required that if an artist discovered their work on a platform protected by the safe harbour clause, they had to issue an individual take-down notice for every instance it was uploaded.
Yes, and this is extremely complex, and requires a lot of detective work. Google benefits from this, and something should be done. YouTube is a jungle of pirated music made semi-legal.