It's all about (mis)communication.
I can sit here and say "by forcing developers to limit some aspects of their design while streamlining gameplay, the success and longevity of this console generation has negatively impacted the type of games I like to play on my PC".
What do a lot of console-only gamers read? "You'd have to be an idiot to enjoy the dumbed down gameplay and shit graphics of a console, you retarded mouth-breathers. Go fuck yourselves." Bit of a disconnect there. Why can't I simply express my disappointment with the state of things without someone taking it as a personal attack?
More specifically, with respect to DA2, I don't believe there's anything inherently wrong with a good action game. I do think it's lame when a company takes one of the only games of its kind and dresses it up for mass consumption at the expense of an existing fanbase. It's not innovation because there are already sooo many "combat leads to cutscene leads to combat..." action games on the market. It's more like homogenization - all the games becoming the same in order to maximize sales. That's all well and good for a lot of industries, but I don't think it's healthy for creative ones like music, movies, comics, or video games. These industries thrive on variety, originality, and quality. Those are the things that speak to us as a collective people over the long haul.
Another thing: DA2, as a raw action game, isn't very good. Next to a legitimate action/rpg like Demon's Souls or Darksiders, DA2 plays like shit. It's the tactical play that makes DA games somewhat interesting, and that aspect was pretty well toned down for the sequel. It obviously plays much better on consoles now, but the PC experience is just meh.
If you've never played Origins on nightmare on a decent gaming PC, it's kind of hard to quantify the difference. I played the first 15 or so hours on 360 before switching to the PC version, and it was like night and day. Going from 1 to 2 on a console was nothing but good times. Making that same transition on PC felt like losing something that's relatively rare nowadays. That's sad.
Anyways, TLDR version: people get wrapped up in the things they like to the point where consoles and franchises are somehow integrated directly into their egos. It's pretty clearly insecurity manifesting itself as aggressive behavior; "if someone prefers things be different, he or she is making a declaration of war against my own preferences".