I can understand the appeal of why people like Bioware games so much, but I also agree with the OP about a few points.
The first Mass Effect seemed more like a buggy concept demo than an actual polished game. While the campaign certainly had its moments, the awkward side questing, the cut and paste interior environments, and the clunky combat really drew me out of the experience. I never felt immersed in the universe or attached to any of the characters, with the exception of Wrex and Captain Anderson. It felt more like I was going through the motions to either progress the story or level up. While it was definitely better than the average game, it certainly didn't deserve some of the very high scores it received. Mass Effect 2 however, addressed just about everything wrong with the first game. It definitely deserved the praise it received, though it wasn't perfect either.
Dragon Age: Origins is more a matter of personal taste. It's not a game that you can faithfully experience unless you play the PC/Mac version on the hard or hardest difficulty. My gripes with the console version is that there is no overhead view and the difficulty is scaled down considerably. That and I believe that Dragon Age's saving grace is its gameplay and not its story, which is almost the opposite of the first Mass Effect. While the story itself is written pretty well, and some side quests and characters are interesting, the experience as a whole felt very bland. On top of that, your dialogue choices rarely have an impact on what happens in the story as you usually arrive at the same outcome. Plus, it's hard to take whats going on in a conversation seriously if your character is covered in blood or glowing from an aura. If they were trying to go for a realistic approach (for whatever reason), they failed miserably.
Bioware is a company that has earned a reputation for creating solid titles. While they have been guilty of releasing a few stinkers (Dragon Age 2, KOTOR 2) there is a level of consistent quality you can expect when you play a Bioware title. Do I believe that people are a little biased to Bioware? Most definitely, but you could say the same thing about anyone loyal to any developer. It might not be that a particular game they release is 'bad', it might be that the subject matter is not akin to your personal taste.