@"primitive/archaic 2D" vs. "3D engines are way more complex, way more immersive, and offer WAY more possibilities for immersion."
I guess that depends on your perspective .
When you investigate 2D and 3D a bit more, this debate becomes kinda shallow, I think, since both worlds come with great complexity, just in different ways. In general, I think, you could say 3D-engines are more complex with regards to math and production performance (engineering & economy) while 2D is more complex within a mindset that appreciates freeform, roughness, and personality (art)... speaking black and white.
So generally speaking, yes, 2D-graphics are more "primitive" from a technological point of view, but we got a positive "primitive" there, since the staff's time and energy is now released to concern itself with making the 2D-perspective's art and gamedesign *complex* in its own way.
If you've played the 2D games like BG2, P:ST and the likes (or even RTS games like Red Alert), it wasn't just the games themselves, it was the POTENTIAL you might have glimpsed there, potential which I feel never was explored in many ways. Visual potential as hinted at by that "screenshot" of PE.
Besides that, I crave for quality 2D games because of expectation and experience. One thing I grew accustomed to expect from high quality 2D games is something NOT ONE SINGLE 3D-engine adventure/rpg game has yet provided for me [EDIT: Ok, concerning games like The Witcher 2 or the new Deus Ex...I have to admit a few exceptions exist]: a high level of depth in adventure and personality (and demanding gameplay, I'd like to add) - and thus: immersion (in a different, more fulfilling way than, say, the immersion of Skyrim's pretty 3D landscapes). I should write this in big letters. PERSONALITY. As I argued, personality seems like a strong point of 2D art. If personality is included, it makes you wonder, since neither you nor any science or market research really knows about other personalities. I would love to wonder about an rpg/adventure game again.