They haven't. Who would want to be the person who takes it to court and ruins the existing scheme, which basically works?
I agee. The DMCA is basically designed to protect sites like Youtube from users' copyright violations, but they've implemented a clumsy system anyway. My assumption is that they don't want to be sued again, even if they would win. Also, it's probably smart to keep big corporations happy when you sell their movies/songs/etc. and take a cut of each sale.
"I think" is frequently implicit when talking to ther people. But fine, it's not like I'm talking shit about a game or something. This is a bit more serious, so I'll reel it in a little.
It's my opinion that Let's Plays violate copyright law and are not fair use, so Campo Santo isn't abusing the system by filing takedowns against shithead racist Pewdiepie. I also enjoy many LPs, but that doesn't really change my opinion that this is a very gray area.