Maybe a solution could be weighting the vote according to the user history: a user leaving a single vote on a single movie shouldn't be as influential as an user that voted on a wider range of movies over time
This kinda happens already, or at least it used to many years ago; you have to be an active user for your vote to count.
The most obvious effect is movies that drop in the rankings 30 days after release; people who just saw a movie give it 10/10 and then stop participating, so 30 days later they are no longer considered 'active' and their vote stops contributing to the overall ranking.
If someone only gives 10s or 1s to everything, their vote of 10, should probably have less weight, than someone who distributes their votes more evenly.
This is not correct. Many people dont bother to vote or review unless the movie for them is at an extreme goodness or badness, so the hassle is worth it. I ve watched a lot of so-so or simply good movies, but I only have voted 5-6 times and those got either a 10 or a 1.
The solution is recognizing that a 'honest' or 'good' metric is not possible. Thing is, to produce such a list you need to have some function f, which maps the complex opinions of each and every user of the site into an orderable set, usually integers smaller than 5 or 10.
The most obvious effect is movies that drop in the rankings 30 days after release; people who just saw a movie give it 10/10 and then stop participating, so 30 days later they are no longer considered 'active' and their vote stops contributing to the overall ranking.