That means the game mechanics is easy to break to create munchkin characters. Wich is quite right. It is all up to the player, though.
But the "easy" part is the whole problem. Try creating a munchkin rogue in 3.5 DnD, and then try create one in DAO. For the first you need to have academic knowledge on the subject, but the second just needs more dexterity. This is streamlining in my book.
Shows how badly implemented attributes are in DAO. A good example of optimization is Fallout NV. You need to know everything about the game to make the best possible build and you don't optimize for combat efficiency but for more options to deal with situations like you do in 3.5 as well. You use the stats to unlock stronger bonuses, like getting extra endurance for more implants, sacrificing charisma to get more intelligence because the skill gain from int will outshine the bonus from cha in the long run etc. That's the process required in games with good implementations. The equivalent of replacing spot with mindbender dip for your skillmonkey and making an illusion nuker with shadowcraft mage in 3.5.
A bad main feature makes the game boring and diminishes my experience. Objectively this matter affects combat more than roleplaying and concept building especially after considering the direction DA2 took and since the effect is proven negative, is in the best interests of everyone to ditch it as long as they fill the spot with something else that is supposed to work better.