I really liked this series in college though I started playing the DQ6 remake recently and I'm kind of wondering why I liked it in the first place.
It's like, this is my experience playing DQ6 -- I'm breaking it down into some kind of... tree structure, mentally, where I'm only presented with two choices at the same time, and the correct choice is either obvious or both choices are equally correct. I get to a town, I'm going to talk to every NPC, check every barrel, check the well, etc. Same thing. Whatever order I do this in is irrelevant -- the actual expansion is irrelevant -- because all nodes will be hit, no matter what arbitrary path between the nodes is taken.
This applies to dungeons and castles as well. The way you end up exploring them.
Combat breaks down into a simple attack-heal cycle with limited viable choices. You have class system, but there's a finite set of maximally useful party configurations for that, etc.
I don't know, I just don't think the passive, reactive, menu-driven gameplay inherent to the RPG genre is that engaging to me anymore. It just feels like going through the motions of doing something without actually doing anything.