Just pointing out that Ratings only purpose in this jam is so you can take a look at submissions page and click "submissions in need of voting" to see which games havent been playtested yet.
Otherwise the rating doesnt have any purpose. Although, technically, itch.io jam system automatically does pick a winner based on ratings, but this isnt meant to be a competition, but just playtesting, hence many are just giving either what ever rating their mouse happens to hover over, or same rating to every one every time.