Anyone else's kid scared of creepy YouTube channels?

My 5yo saw some weird puppet video on YouTube Kids (which is supposed to be filtered!) and now she's having nightmares. Like actually scared to go to sleep. We haven't let her watch YouTube much since but I'm paranoid about what else is on there. We switched to Netflix Kids and Puffin Rock exclusively but I feel like I'm being paranoid? Should kids just be tougher about this stuff or is YouTube actually dangerous for young kids?