There's not double standard because Nintendo's games don't need stories to cover sub-par aspects. It's not important. It's not what makes the game. It never has and it never will. Even RPGs with 'good' storylines but bad gameplay are complete trash because they're not worth playing.
Besides, I always hear this whining about story and wonder what games people were actually playing. Zelda games have had pretty good and interesting storylines since LttP on the SNES, and Metroid's explored multiple style of storytelling, from the dialogue heavyFusion to the user-prompted filler scans in Prime.
Really the only games I can think of loose on plot are Mario, but considering what actually goes on in the franchise I can't believe people want something even more wonky. Can you imagine wackiness of Mario combined with the laughable writing of Metal Gear? It would make for a nice parody but nothing like the 'serious storytelling' people keep crying for.
Tag - "No trolling on my watch!"
