But the two can't be compared......a movie no matter how good the script is will always depend on the actors. A game does not depend on voice actors it depends on gameplay. So is the gameplay is fun then that is what will make or break the game.
And I have to disagree with you saying if the game was a 93 it would have had 20-30% more sales. There are games that have scored amazingly but sold poorly and games that have scored low or average that have had huge sales. So having that 93 doesn't mean that there would have been more sales. Because to be honest from a critical standpoint the game scored very well just not to YOUR standards.
And if the game had the best launch in the UK of the series then I doubt Ubisoft is thinking about lost money when they just got MORE money than they ever have with the most sells it has ever got in the series first week in the UK. So it looks like the "low" score as you call it is not hurting the sales. But again it is your right to feel that the score is low by your standards even if it is not low at all by critical standards.
An RPG is a story driven experience, story and acting is almost as important as in a movie, considering you spend even MORE time in cinematic and conversations in an RPG that you do in a movie. So I judge RPG's largely by story and acting.