Where this leads is characters who don’t sound like anyone. The same way a cartoon doesn’t need to look like an actor, a voice can be pieced together to broadly resemble many people, without anyone going ‘hey, that’s so-and-so.’ But it’s just a virtual throat. It’d let Billy West do Hermes if something happened to Phil LaMarr, but he’d have to fake the Jamaican accent himself. Playing the character becomes a matter of performance - without having to pinch your larynx a particular way.
What that enables in the near-term is letting Julie Kavner do Marge’s voice properly. The poor woman is barely recognizable after forty years of vocal fry.
What it means ten years from now is kids bickering about who did the best Blorbo McFlorbo, when all iterations of the character sound exactly the same. Could be a show with two VAs total, freely trading who does who, when otherwise they’d be talking to themselves. Could be a troubled production with a revolving-door cast. You’d never know unless you checked the credits. Except in that one episode Blorbo spoke Spanish, because everybody quit and it turned out the janitor was union.
AAA just means it cost a shitload of money. That only happens when people figure there’s a market for it. Publishers don’t spend one bajillion dollars unless you can promise ten bajillion with a straight face.
The best bet for that is probably comedy? Same as it ever was, I guess. Disco Elysium is a modern point-and-click game with some dice-rolls tacked on, and the draw is your absurd inner monologue. Full voice-acting was definitely the right move.
What’d fascinate people nowadays is an explosion of interactions. Have a Monkey Island level of inventory and NPCs, and have some unique stupid thing happen for every possible combination. If some of that accidentally implies alternate solutions to obstacles, great, roll with it. It’s like an immersive sim! A famously profitable and stable genre.