It doesn’t have to be like Fallout 4.
With Fallout 4, Bethesda broke a long standing tradition and finally went for a voice acting protagonist in one of their games. The end result is… decidedly average. The quality of the voice acting is up for debate, and the dialog system in the game also suffered as a result. The long and short of it is, fans were not happy with the move- and for future games that Bethesda makes, including the upcoming The Elder Scrolls 6, they would probably rather that the company move back to an unvoiced protagonist, and the classic dialog system.
The question is, is that necessary? For starters, remember that it is important to divorce Fallout 4‘s dialog system from its voiced protagonist- sure, one thing may have led to the other, but it is entirely possible to have voiced protagonists without having a simplified dialog wheel- games like Mass Effect and the Witcher 3 are evidence enough of that.
The Witcher 3 is, predictably, the point of comparison here- after all, it is an open world fantasy RPG that greatly benefits from giving us a voiced main character, allowing us to lose ourselves not just in the world, but also the character and its motivations. Why not do something like it for The Elder Scrolls 6? A character who is voiced, but with a Witcher style dialog system, would be the best of all worlds- although I admit, I would rather that as far as dialog and voiced protagonists go, they change nothing at all from Skyrim.