Forgive me if I'm missing important context here because my crpg experieince mostly goes back to dragon age, but those voice styles were always only for random barks of about a line each, not stuff that goes through an entire game.
Sure, for the most part that's true. Since games often do the "Silent protagonist" thing when it comes to actual dialogues.
With exception of Solasta of course, where it influences what dialogue options are available and the things your characters say.
And if we're limited to the vocal "style" we choose at the beginning, that could prevent us from letting our character's personality and demeanor change throughout the game. In pillars of eternity for example, I often have my characters there go through major changes. In my favorite playthrough, my Watcher went from being sullen and withdrawn to being fiery and passionate. That kind of option would likely be entirely denied to me if I had to pick one style of voice/tone at the start of the game and stick with that.
I suppose that would be dependent on how the "Style" is formed. Something such as Solasta's personality picker could very much be adapted to be malleable given that it's based on picking certain aspects of personality (Like Egotistical, Violent, Lawful etc) that it could use generic "Alignment Shift" tech when utilizing other dialogue options and allow for shifting into alternate styles once a threshold has been reached (It'd probably come across as a bit janky and abrupt... But to be fair, so is any sudden shift in disposition)
As far as going from sullen and withdrawn to fiery and passionate... It's not even particularly likely that such a change would effect vocalization. Rather it would change what options you pick and get vocalized (I.e. You stop picking the dialogue options that avoid emotional responses and transition into picking the more emotive ones). Which is already possible in games with voiced protagonists (For example Cyberpunk 2077 you have options to pick those types of dialogue options and V expresses themselves accordingly)
I think Solasta isn't a great example because Solasta isn't really about creating character personalities. I actually think you using Solasta as an example here illustrates where we diverge in our view of these games and roleplaying within them. I don't see the party in Solasta as my characters the way I see Tavs in BG, or the PCs in Dragon Age, etc. I'm not roleplaying them, I'm not actually making dialogue choices, not really. Their personalities are wooden and weak. They can get away with full voicing because the game is fundamentally on rails at every point. I actually like Solasta better than I like BG3 for multiple reasons, roleplaying is not one of them, and I do not want a game that focuses on roleplaying using Solasta's system. I can't recall a thing about the personalities of any of my characters from Solasta, but I can recount the personal arcs my characters in Pillars of Eternity went through, Kingmaker, Wrath of the Righteous, etc.
As for going from sullen to passionate, those two demeanors definitely impact vocalization. If you're sullen and withdrawn you're going to talk slower, softer, more maybe hesitating more at times, while being passionate and energized would lead to you being louder, more certain and confident in your words.
I think that silent protagonsits are simply better for crpgs 9/10 times, and changing my mind on that is going to be as difficult as changing your mind on your opinion here.
I'd still like your input on exactly why you believe so. Since I'm struggling to find where the benefit is for a silent protagonist.
I don't care how the npcs or the game reacts to my character
At which point you can emulate your silent protagonist by having a voiced protagonist and simply skipping their dialogue and headcanoning your own thing in place. If actual dialogue is irrelevant to you, then there's no downside to simply skipping all dialogue and headcanoning whatever you want.
I know that there are always limitations because this is a game, but it seems that you consider those limitations far greater than I think they are.
Seemingly it's because I care about dialogue as a whole and not just what my character is doing.
As a whole, I care about what my character does, and how other characters react to what they do. This creates more of a sense of being in the world, which I find far more conducive to roleplaying than simply being an observer pretending like what I think is occuring.
I personally can't get into headcanoning my own actions into the game if every other character doesn't respond to them. Since it's so jarring to have that occur (To me at least. Perhaps some people like trying to fight the narrative of the game by pretending something completely different is happening)
Possibly because I see a video game as a means to explore a writers story rather than a means to create one. For creating a story, there's Tabletop RPG's where it's all about becoming a character and interacting with the world directly. Where whatever action I think up, is what actually occurs and things actually ensue because of that.
I think that going fully voiced would take away far more options and the benefits wouldn't be worth it and would result in crpgs that lose out on the things I fundamentally value in crpgs.
Fully voiced doesn't take anything away. Especially if you're the type of person who doesn't actually care about cohesive dialogues. As dialogue skipping can emulate silent protagonists.
Meanwhile, fully voiced can directly add to dialogues by allowing for more dynamic sequences. Something that cannot be recreated with a silent protagonist staring at people like they're in middle school giving a presentation.
If fully voiced is done well, with adequate options for voice types (Accents, demeanor), personalities and actual responses. They can create a far more immersive and enjoyable dialogue experience than a silent protagonist. Whilst still retaining a high level of personal creativity, enabling creating a character that has a relatively unique personality.
I seem to have not expressed myself well enough here. When I say that I don't care about how the world reacts to my character, I mean it in the sense that I can accept people reacting to my words in a way I didn't intend them, because that happens in real life. You can say a thing and people interpret it differently than you meant it. So if I say something intending to be jokey and an npc takes it as an insult, that's fine to me. It's not that my character was arrogant, the npc just took it the wrong way.
Let's look at another example. I like Telltale games a lot. The two telltale Batman games especially. Those are games with voiced protagonists. People complain about illusion of choice and different dialogues leading to the same outcome but I don't care because I don't view the outcomes as being important, I view my character's response as being what's important. No matter what the result of their action or words, the fact they I was able to choose those words and envision what that means for who they are is the thing that's important to me. So skipping dialogue isn't going to emulate the silent protagonist experience for me. Firstly because having to be poised on the continue button to skip dialogue is not condusive to an immersive, enjoyable experience of taking in a story. Secondly I have yet to see evidence that a fully voiced protagonist wouldn't result in a major curtailing of dialogue options. As much as I love the latter dragon age games, it's evident that when they went fully voiced for their protagonists, the dialogue choices became very limited compared to Origins. I'd just rather have more options even if they lead to the same outcome.
Finally, I'm not convinced that your idea of a fully voiced crpg protagonist "done well" is even possible at this stage anyway. I think what we'd actually get is something way more limited, without the capacity for varied, choosable backgrounds, little variety in voices, and loss of the choices that make this genre exciting and unique. Look at Cyberpunk 2077, you're always V, and the background system for that game was downscaled to have minimal impact. Compare that to Wrath of the Righteous. The number of choices in that game is immense, as is the variety of them. Imagine having just one voice actor try and perform in a way that could make consistent sense across all of those paths, now try and apply that to multiple actors who all have to try and go for multiple different tones. Maybe in a decade or two that will be possible, but until I'm convinced you can create a game the scale of Wrath of the Righteous, with all of its options and possibilities, and still have a fully voiced protagonist, I don't think we should even entertain the notion, because the result will absolutely be watered down.