To OP: Valid arguments, but I'd like to play the devil's advocate and counter your arguments in the post.
While not all video game stories suck, it is true that there's no good video game story. The reason is that video game stories are constrained by gameplay. A game must be entertaining/enjoyable or otherwise it's not a good game. While on the other hand a good story doesn't have to be entertaining/enjoyable. This inherent constrain of gaming limits the types of story that can work with games, which resulting a lack of good video game story.
While not all video game stories suck, it is true that there's no good video game story. The reason is that video game stories are constrained by gameplay. A game must be entertaining/enjoyable or otherwise it's not a good game. While on the other hand a good story doesn't have to be entertaining/enjoyable. This inherent constrain of gaming limits the types of story that can work with games, which resulting a lack of good video game story.