Film archivist Fran Blanche posted content featuring the Apollo moon landings to YouTube, and reported being besieged by frauds using ContentID, the platform's private copyright enforcement and monetization system. No sooner than she makes a new transfer of a classic public domain film from NASA's own reels, for example, than it gets dinged by some shady agent—who in one case turns out to represent the makers of a "VHS shockumentary" which reproduced only low-quality broadcast footage in the first place and has absolutely no legal claim to the original material.
"The way it's set up, the claimant has all of the authority," Blanche says. "They are the sole judge and authority."
Blanche cites another recent case of hers where Sony Music claimed to own audio of wind blowing in a 1973 public domain movie. A Sony Music artist sampled the movie's audio in a 2003 heavy metal album, and it's on that basis that Sony made its claim to own the audio. Even after she filed a counter-claim, she reports, YouTube sided with Sony Music.
Whenever something like this is reported, a clever commenter always pipes up with "make a new thing that samples Sony Music and now you can claim it!" Alas, you're forgetting who YouTube's ContentID system was made for.
YouTube is just not fit for anything important. Treat it as an ephemeral money-making endpoint for Content and don't do anything there that you'd be disappointed or troubled to see disappear.