Why is Netflix Dumbing Down its Rating System?

Remember when there were shades of grey in society? When one’s opinion of a piece of art wasn’t reflexively limited to “it’s great” or “it’s terrible”? When our political system wasn’t rigidly, immovably partitioned into an eternal, 50/50 war for supremacy, where new ideas are derided and cast out?
More importantly, remember when you could reasonably rate a movie on Netflix? You should, considering that you were able to do it until this week. That is, before Netflix removed the star system for good. Say goodbye to stars, say hello to the vastly inferior “thumbs.”
Let’s just start off with the obvious: Every star rating you’ve made over the last decade of using Netflix has just been erased. The thousands of films you’ve rated to make sure Netflix gives you the best movie selections it’s capable of giving? Those are gone forever. That weird little hobby you had of seeing how many Netflix movies you could rate? That’s gone too. The entire service essentially just got a complete reset, in terms of its perspective on your taste. Even if you’d rated 500 films with perfect 5-star ratings, under the new system, Netflix no longer has any of that previous data to suggest those films to you. In short, it no longer has any idea of what you like, even if you’ve been using the service for years.
EDIT: It’s been pointed out that the star ratings actually do still technically exist, if you visit your profile and click on “ratings.” They are, however, functionally pointless now, given that they don’t have any affect on the newly minted “match percentage.” They’re just a reminder that Netflix is no longer bothering to use that data.
This is obvious as soon as you look at any of the genre pages—allow me to simply use the horror page as an example, given that I recently wrote our list of the best horror movies streaming on Netflix. The movies it recommends extremely highly to me are now, by and large, straight to VOD garbage with titles such as American Poltergeist (97% match!), Anguish (96% match!) and The Charnel House (96% match!). Meanwhile, the movie I just rated as the #2 best horror film streaming on Netflix, An American Werewolf in London, is rated as a 65% match. My #1 film, The Shining, is merely 81%. Which is to say, Netflix’s new system is pretty sure I’m going to enjoy The Rezort, The Ouija Experiment 2 and Little Red Rotting Hood more than boring ‘ole Stanley Kubrick.