(Re-reading this reply I guess we will be agreeing to disagree here.)
Whilst FFVII did have branching dialogues, honestly, the only one really worth writing home about was the Gold Saucer date mechanics. The rest of them merely as backstory and had very little impact on your characters main scripted personality or motivations. Compare that to say something like an Elder Scrolls game where most of the time you're essentially given a blank canvas to project your idea of your character onto and is a far better example of the game world reacting to how you play. In the case of the latter I could understand why people would get hung up on it when that gets taken away. But again there's voice acted RPGs that have had divergent paths too - does the voice acting take away from that?
I also think, in RPG contexts at least, there's far more to this than just singling out voice acting specifically. You even mentioned it yourself Bolivar:
This is very much an issue when it comes to video gaming. Books, being a very non-visual medium, leave a whole lot to the imagination. For example if a character is a 5'5" brown haired medium build guy - I'll probably imagine a completely different look for him than the next person will. However in games you're immediately shown how the character looks - likewise with locations. We've progressed a long way from the sprite art which only so much was capable of and still left a large amount to the imagination (as with books) to the point of either very realistic or highly stylized art directions that can accurately convey facial expressions and emotions. Likewise we have a whole section of the gaming audience that find it hard to go back and play older titles based on the dated graphics and/or mechanics which undermines the element plot has to play - but that's a whole other tangent altogether.The only wrinkle to this argument is that with the advent of advanced graphics that can realistically portray a character's speaking and facial expressions, it would almost seem creepy to not hear them actually speak.
However just like it's taken film makers over a century of refining and redefining their craft - the same is going to be true of video games. For some the trade-off between things being left to their imagination is too great, whereas others prefer the new level of immersion and cinematic experience it provides.
On that note is the issue with Advent Children really because it gave the characters a voice or because the plot of Advent Children as a whole was a terrible exploitation of vague loose ends from FFVII to allow for a cinematic anime action style fight between Cloud and Sephiroth? Would that have changed if it wasn't voice acted?
Honestly I just don't feel that singling out the FF series is a good lens through which to look at this. The issue with VA in FF is more down to implementation and quality than it is with what it may or may not fundamentally detract from the experience. FF games as a whole still largely use the same character archtypes and if anything all VA has served to do is draw highlight to this but the base core is still there. I do agree that in video games as a whole VA can and does detract from the experience.
This is without even touching base on the shift in gameplay design as we've moved into a very Hollywood-esque blockbuster driven market.