content: Unfortunately for the average joe, the way things work legally in the globalized, bureaucratized West is "if there's no explicit law against it, it's allowed until someone challenges whether it's allowed, and sometimes even then you can do it." There are lots of companies for example that make claims or statements in their EULAs or ToS that are of quite dubious legal nature, but 1) no one takes the time to read through the book and find them and 2) nobody bothers to take multi million+ companies to court over "I think this might not be legal." I imagine it's the same way with copyright trolling. Also, DMCA claims are a now well-known tactic to deal with content you don't like on YT. Plenty of people have issued false claims against people they just don't like, you or I could even do it with zero evidence or anything to back our assertions, and YT would take it down.