Here's how I think about the unvoiced protagonist. Framing it this way in my head has greatly increased my enjoyment anytime there is a silent protagonist.
When there is a moment that the protagonist would speak, or when a character *pretends* that the protagonists speaks, imagine what you yourself would say if you were the protagonist. The lack of a script allows you to insert yourself more directly in the story. I don't think it always works, but I've found that having a silent protagonist can allow myself more freedom in role-playing. Because I'm not constrained by the words the Hero chooses, I can instead imagine the ones I would use.
I totally get your mindset and appreciate the tip, but it's not something I'm really good at - at least not anymore.
I remember being annoyed that Rockstar chose to give the protagonist of Vice City a voice after the mute hero of GTA 3.
However, I've changed a lot since then and have really come to dislike main characters who don't speak.
Link in Wind Waker (and to a lesser extent BoTW) works because he's very expressive and the game is written in a way that acknowledges he doesn't speak. I recently played and adored Astral Chain, but the playable character's lack of voice acting hurt it. In fact, your sibling is a much more interesting character in that game simply because they can speak. However, Platinum just about gets away with it because it's primarily an action game and you're framed as a rookie officer, taking orders from more dominant characters.
Dragon Quest, at least from my very small taste of the game, puts you in a relationship-driven, sprawling RPG, where you play as a specific character, with his own backstory and friendships. Worse still, he's put in cutscenes where people talk to him in such a way as to almost demand an answer he can't vocalise. He's meant to galvanise people, but can't speak and scenes where we get a 'XXX told so and so about the plan' just feel like such a weak alternative.
During a fateful trip back to his home town where he discovers his heritage via a worn-out, old letter, he's got Erik stood next to him, kinda of guessing what it's all about because the hero just can't tell him. He says 'don't worry, you can tell me about it later' but we know as players we will not get to see that moment play out naturally. I also don't think the character is particularly expressive enough to get away with it.
I suppose I'm not actually good a role-playing. I'm not in any way saying my above thoughts are 'correct' as it were, just that I feel there's a massive disconnect for me, created my a voiceless protagonist.
Curious to hear if fans would like to see the next pre-defined hero have a voice or if they'd prefer it to stay as it is...
