I've heard that one popular channel accidentally sent a take down for their own content once, then some companies just scan for keywords. I forget where but remember reading that some blog was a take down because some studio ran a bot looking for keywords and assuming anything that mentions their movie titles is a download even though that site didn't host an actual downloads of the movie. So say for example you had a movies review blog, just mentioning the movie can cause some studios to flag it in bulk without reviewing your website or considering any fair use.
Then even if you license royalty free music, there's bot's that flag it so you can to dispute even if you paid since they don't know you got a license, they just auto assume that you didn't. Then also sound loops so, like Garageband Loops [0] you are allowed to use them in a larger project, but not the loops standalone... but some songs use these loops and samples, so say some artist used a Apple Loop in their song and got popular to be part of ContentID, then that artist starts flagging content from Apple they never created in the first place. Sounds like YouTube requires your music doesn't contain third party licensed royal free stuff within them but sounds like they still get submitted to YouTube anyways. And this isn't just a Apple Garage Band problem, happens with other music programs too like FL Studio and a bunch of others. Wouldn't surprise me if two digital drums (I guess music programs call them "virtual instruments" sounded too much alike if it would be flagged either, since remember hearing nothing but white noise got flagged once...
[0] https://support.apple.com/en-us/HT201808