Stories do not need to be good for a video game to sell. These days, the game doesn't even need to be original, you can just sell a remake or a remaster and print more money.
Stories aren't even a substantial factor for maximising sales. Paid DLCs are often self-contained and not necessarily even based on the story.
There is a reason why every game released now is a "cinematic" title with a generic bad story and most likely with online multiplayer (co-op and/or PvP) and microtransactions for player customisations.
These games have the "breathtaking cutscenes" and "next-gen visuals" to give game review websites their headlines (game review sites are basically as crooked as financial ratings agencies) and then the game prints money with initial cost, cost of paid DLC, and the cost to give your character flashier armor than the other guy.
In the beginning, people developed games with passion. They focused on make the game fun to play, rewarding to play. We didn't know the best ways to do things but we tried.
Games were difficult because overcoming a thumb shredding fight is satisfying, figuring out an obscure puzzle is satisfying.
But when video game publishers etc got big enough, they were able to cherrypick what they published, so naturally they go for whatever will generate the most revenue with the least risk.
This means games are easier, so more people will play them and fewer people will give up on them.
Games don't have puzzles that aren't solvable in seconds because this represents a distraction from the combat which some research has likely shown to give the general population more pleasure than anything else.
And games don't try very hard at stories because it probably costs a lot to come up with a good story and a good story will likely involve game segments that are a little harder to put together than the generic linear levels the publishers had in mind.
Publishers probably also figure it's safer to keep things basic in terms of story because they have data to show that people bought into and/or enjoyed a story 85% similar in the past.
And they can just add DLC and remake/remaster the game down the line and flesh the lore out. Hell, they can just rely on the community to maintain the game on a long enough time scale.
Stories in video games are bad for the same reason most movies these days are bad and samey. Money dictates everything on a large corporate level and video game production has reached that scale.
You still get indie devs who can go off the beaten path, but I feel like 70% of these indie endeavours result in a 2D platforming/metroidvania game because it's easy to make. Which is fine but one could argue that this results in some samey stories.
There are obviously other indie games that are good and different but it's still rare to see a great story -- the dev may not care much about the story, they have less time to write a good or original story because the game is likely their side-project, or hell maybe they just suck at stories.
ultimately the story isn't super important to whether a game is enjoyable to play. it is a factor to whether the game is fondly remembered, and to whether it moves/touches people.
what matters is passion, artistry, soul. hard to define, but basically if something is made with every effort to be perfect, to realise a vision, and to be made enjoyable and fun to play, regardless of cost-efficiency to some corporate timeline, it has a chance of being a great game. if it has a great story, even better, it can have 10/10.
I don't care what the graphics are like, I don't need to see the pores on a characters face or their nostril hairs. far too much time is put into this aspect of games.
I care about whether the game is fun, whether it's all but addictive to play again. is it challenging? do I feel good when I become skilful enough to overcome challenges? how the hell do I get out of this room? did I seriously just have to read through books I luckily coincidentally own to find the solution to this problem?
then comes the story -- and to be honest, this is mostly because there's par for the course. if it's really bad, like horror channel b-movie bad, then there it makes a game struggle to stick. but things like good execution and quality voice acting can help recover a mediocre or unoriginal story.
I value originality, I think I am just a little bit too jaded to expect it from games or indeed any media at this point -- it's nice when it happens, but if it doesn't, as long as it's done well and there's passion, as long as the game tries and is fun to play, well made, I'm not gonna hate on it for having not-shakespeare story.
but there's a threshold, like I said. Halo is a good example of a shooter with a story that is pretty familiar prima facie, but it earned a pass by being fun to play and the story has more interesting features than immediately meet the eye.
metal gear solid, the PSX gsme -- a very familiar plot, certainly for a while into the game anyway, but the execution and storytelling was so good you didn't care.