This was the bane of Gmod Theater. Everyone who wanted to watch videos in Gmod Theater always had the queue tabbed open so they could downvote everyone else's suggestions, then put theirs up at the last second so the player would prioritize the videos that gamed the system. The only way your suggestion would ever get seen is if you then also gamed the system. It was poorly designed and I am sad to see that system has been implemented here with zero apparent revision.
Upvotes already allow for videos to be distinguished by preference without being as prone to burying every other video in the queue because of a few selfish people. Maybe just keep those? What constructive purpose is giving a video negative points going to serve when everyone has access to that power, and the ability to react against those downvoting them?
The system of just having upvotes isn't entirely perfect, but it's a hell of a lot better than allowing people to bury other videos instantly.
P.S. Throw-able popcorn when?