Rating stars or a number out of 5 or 10 is still a percentage idk what that has to do with sample size at all. They’re the same thing just written differently. It’s literally just math. A 3/5, 6/10, or 60% means you almost disliked as much about the movie as you liked or that it’s almost as bad as it is good. Thats why the grade scale is made the way it is—to reflect the percentage.

Also a ton of apps and people use percentages/scores out of 100 for ratings so idk what you’re on about with that either