D2 story was not that good, but at least, it was not annoying, pathetic and laughable. Now i feel i'm playing the Twilight of videogames
D1 had very little memorable dialogue between characters. The narration was all it had going for it. The dialogue that did exist between characters was sparse at best, weighing heavily on one-liners to sate the player's literary obsession.
D2 added much more characters, thus more dialogue between characters. However, the characters still remained unmemorable. Again, the dialogue that did exist was sparse, but at least there was more characters to talk to.
D3 traded drawn-out narration for character dialogue (or a least attempted to create a balance), and had little lore books hidden around the game to tease and insight you. Characters had a lot to say in this game. And as far as everyone is concerned, the game is not over, so the story will be riddled with plot holes and cliffhangers to pave way for expansions.
All of the character dialogue and narration was completely optional and if you didn't take time out to listen to the dialogue or narration, the attachment was non-existent. You don't even have to care, because the game gives you the option not to. It's a game that uses a story to push itself, not an interactive book that uses gameplay to push its story. If you choose not to take time out and absorb the dialogue/narration/lore, don't come to the forums complaining.
You didn't have to play D1 to play or understand D2, and you don't have to play either to play or understand D3. The journal feature did a fantastic job at both informing you and teasing you of the game's lore.
The only thing I will agree is that with each game more and more cheesy literary devices seem to be added in an attempt to confuse or delude the player from getting too paranoid or upset concerning "what if"s and plot holes.