Not believing in ghosts or spiritual bullshit one single iota I doubt I'd be scared like them. The flickering lights would worry me as a potential mechanical failure in an elevator, and the sheer "wtf" factor of a kid appearing out of nowhere would make me jump. No cowering because of a "ghost kid" though, you can tell even with a tiny windowed version of the video its a kid in makeup. Of course its easy to say something like that and an entirely different thing to experience it firsthand.
Still though since there ARE a bunch of superstitious people out there this video was golden.
Edit: Just realized I'd probably notice there was no momentum on the fake elevator either.