By no means would it necessarily make for a worse experience. Mass Effect wasn't diminished because you couldn't side with the Reapers, for instance. And then there are games like TOR, where the Empire is clearly the evil side, but the vast majority of its players don't mind because the choice was made clear from the beginning.
So that it may not necessarily make for a worse experience gives the implication that it still might make for a worse game.
I think the Reaper analogy is a poor one, since it'd be more akin to siding with the Darkspawn which you cannot do in Dragon Age (EDIT: though as people point out, you can actually work together and coexist with the reapers). It'd probably be better served to use stuff like the Rachni or the Collector Base. Though a lot of people feel that those choices were greatly underutilized and ultimately it compromised their enjoyment of the third game.
I think it's also important to note that when playing a video game, people can disassociate themselves from their character and play (and enjoy) behaving in a way that they wouldn't in real life without being real life monsters. One of my all-time favourite gaming experiences was my playthrough of Knights of the Old Republic, in which I played a soldier that attempted to do good as much as possible, but allowed himself to do dark things in the greater good of helping others. In the end, he succumbed to the dark side and ended up using the Starforge against the Republic.
I'll spare all the details, but many aspects of my character's evolution just ended up having such perfect timing that it was just a very entertaining and enjoyable experience. One of those "influential moments" in my gaming history.
Modifié par Allan Schumacher, 02 mars 2014 - 11:14 .
Added Reaper compromise line after reading posts before mine.