Actually the reason they are terrible at it is because they are artists trying to create a game, and aren't good game designers so their stuff is terrible to play. You have to have something enjoyable to play, before you start worrying about the writing. No one plays ET for the Atari, not because of its writing, but because its gameplay is horrible.Thats because they are devs, not writers.
They build assets and mechanics, not enticing adventures.
I'm a writer, but not a dev. Anyone wanna team up?