Responding to the Frame Trap Hottake:
I think if you look at game stories from a wide perspective (taking other media forms into account), game stories are for the most part clearly very poor. No game is near the heights of Shakespeare, or any classic authors. (To be fair, neither is most literature)
On the other hand there are plenty of games that have much better stories than Marvel movies.
I think it depends on context of the consumer. When you walk into a Marvel movie you don't expect great story. You expect muscly guys in tights to punch each other. They usually do punch each other, and then you leave the movie feeling excited. There's generally some faux-emotional moment, but they tend to be extremely shallow and transparent, and that's not why people are in attendance. People would still go to GotG2 even if Starlord didn't have have a daddy issue.
When you start a new game, you generally are expecting the story to be good enough that you don't 'walk out of the theater'. That's basically the standard - if the story doesn't make you angry, then it's serviceable. If the story actually compels you in some way or enhances the gameplay, it's considered to be a remarkable achievement. Since this is what consumers expect, I have no problem with reviewers giving good scores to games that will meet consumer expectations.
When you read a book however, a compelling story is the baseline. The bland stories usually found in games would be completely unacceptable. The story is basically all there is - there is no gameplay or special effects to act as a crutch or as the main attraction.
There is a ton of room for critiquing games as an art form rather than as a consumer product. To me, a game is at its best when story and gameplay are married and they both elevate each other, becoming greater than they otherwise would be on their own. Examples:
The Last of Us. On it's own, the story is only okayish. It's comic booky, though the ending reaches for a higher level. The gameplay on its own is serviceable TPS with survival elements. But when you put those together in a way that they are both building off of each other, it elevates and becomes remarkable.
Metroid Prime. The story is fairly shallow, there's not really any meaning being conveyed. It's just a couple plot points that happen. Pirates blast planet, wake up Metroid. Samus blasts Pirates. Samus blasts Metroid. The end. Yet I would argue this story is excellent, because story is more than plot. The actual story is provided by the world design which feeds directly into the plot and pumps it full of the meaning that is otherwise lacking. Metroid Prime has prongs other than story and gameplay - the environment is really the star of the show, but they all intertwine and elevate each other into a masterfully complete piece of art.
Persona 4. If this were an anime rather than a game, I think it would be okay, but not particularly special. It certainly wouldn't rank with Cowboy Bebop or Your Name or anything like that. Likewise the gameplay isn't that interesting, it's fairly standard JRPG mechanics, though the Personas are a nice hook. Put them together though, and it becomes an amazing experience I may never forget.
(Note: "Putting them together" is extremely difficult. You can't just take a good story, and make the characters have good gameplay. Marrying the two takes a ton of skill.)
On the other hand, there are other games that are masterpieces due 100% to the gameplay. Mega Man X. Mario Bros 3. Tetris. There is no reason to add story to these games. If anything, a Shakespearen level story could potentially detract from these games and make them worse.
Similarly, look at non-video games like chess or basketball. Those have unbelievably good gameplay, with no story. No one wants those to have story - adding story to them would be utterly absurd. (You could argue off-court player drama in the NBA adds story, but that's beside the point)
Then we have video games which have very little gameplay and almost pure focus on story. Life is Strange, Telltale games, etc. Back to these in a second.
This is the part where I probably throw some people off. I've never played a good story-based game. I think we do need to be tougher on those games, because they are not achieving what the earlier games I mentioned are - either pure excellence in a specific area, or a balance of elements in which each element enhances the others to make an elevated experience. They bank everything on telling a great story, and in my experience haven't delivered (although I still like them).
Let's take Life is Strange. I enjoyed this game. I was compelled to continue due to the story. That makes it good right? I don't think so. I think that makes it baseline. Just like when we read a book, the baseline we expect is that we're compelled to continue. That should be considered average and not particularly remarkable. A great book would enrich my life, give me new perspectives, or form a truly deep and unique connection with the world or characters. Life is Strange doesn't do any of that. I like some of the characters, but that's simply because they use relatable tropes (not necessarily a bad thing, tropes can be useful). I wanted to find out what happened next, simply because it used some plot hooks. That's something I would consider to be the baseline standard for any book to do.
By default, game stories are more like comic books than classic literature, because you get to see images of what's happening rather than having to imagine it. I think that's the reason we give it some leeway. Without visuals, Life is Strange would be a young adult novel that we never would even consider picking up. Without visuals, Marvel stories would be an utter joke.
Is that bad? Should we give these games credit simply for having visuals? I think that's the heart of the question. Do we give some video games credit simply for being video games? The answer to that is undoubtedly yes, but whether you're comfortable with that and how you would take that into account if you're a reviewer is completely up to you. I would expect there should be different avenues of critique - does this game succeed as a consumer product vs does this game succeed as a work of art. Life is Strange attempts to tell a story - it definitely succeeds as an enjoyable product, and is mediocre as a piece of 'literature'. Games which attempt to purely provide great gameplay and nothing else are different, because generally the gameplay is the art form as well as the consumer appeal. That's why Tetris is almost universally considered to be perfect.