The quality of Mass Effect 1 and DA: Origins came from how polished their stories were. The gameplay was the weakest point of both games. Don’t get me wrong, I liked playing them, but they do not hold up. Then, or now.
Both Mass Effect 2 and Dragon Age 2 experienced the exact same quality shift. Less quality on the story side, better gameplay. In DA 2’s case, they might as well have handed the writing off to the interns.
It only got worse after this. We all remember red explosion, blue explosion or green explosion at the end of ME3. DA Inquisition existed, the multiplayer was fun (and similarly the only fun thing, to me, in ME3).