Stop ratings and reviews for unreleased movies
As simple as that, open this settings only a couple days/weeks before the actual launch.
Allowing these reviews allows for un-serious reviews and jokes by trolls as can be seen here: https://letterboxd.com/fillupjfry/film/dune-2019/#comment-3255554
Chris R commented
I just looked at the new Halloween film and it already has a bunch of ratings. Why is this allowed? It just encourages the trolls and attention seekers. You haven't seen the film, it's not out, so stop messing up the average rating!
Agreed. It's always some nonsense. Ratings and review section should be completely disabled until release. Most of the time there's an embargo and reviews aren't supposed to be out anyways.
Paul Walker commented
I get that this is tricky to do with festivals and preview screenings etc, but it's so disheartening to look on the page of an upcoming movie and see it flooded with reviews of people simply talking about the trailer or making jokes about what they think it'll be. We all know this is just an easy way to get likes because seeing entries for big name upcoming movies is very eyecatching, but it's disappointing because it causes actual reviews to be buried when the movie comes up.
This is something that seems to be growing more and more common on the website, and it's very annoying.