DA:O is such a turd. It's not completely obvious how much of a turd it is at first glance. It has a nice shiny exterior and some of the initial impressions can be quite positive. Oooh, interesting lore. Ahh, a spell combo system. A large world to explore.
But it's all shit. The writing is arguably some of the worst in any video game ever simply because of how pretentious it is in relation to its quality. You can have games with small amounts of shitty writing, or walls of text written well, but DA:O has WALLS of TEXT FULLY VOICED OVER ABOUT THE MOST BORING SHIT EVER. Every fucking dwarf you click to buy some shit launches himself into a Hamlet-like monologue about his whole fucking family tree and history and retarded children until you just want to join the Darkspawn and kill everything that talks. Never did I sit through such boring shit as DA:O dialogues and cut-scenes. At the time, I even thought that I might be getting too old for games, but then I played some of the Witcher games, and realized that no, it was the shit Bioware writing, and not gaming in general.
Then there is the shitty exploration. You have a giant game map, which turns out to be just a few point-of-interest towns, which are fairly barren, and some tiny wilderness maps in between. The wilderness maps are so small and filled with invisible obstacles, that essentially they function as outdoor corridors.
The combat is shitty because mages are overpowered as all hell, and most other things are underpowered. Stuff like Entropic Death and Mana Clash can one-shot boss level monsters, while my 2h-warrior was a gimp.
Oh, and another reason that writing is so crap, is that the main story is so telegraphed. Think about any DECENT rpg, say a PS:T or a Witcher game, or PoE. The story is complex and has many twists, and at the begining, you have no idea how it's gonna play out. But in DA:O, by the 2nd hour of gameplay, you can pretty much know exactly how everything is gonna turn out.