rock paper shotgun put it best
As for the matter of the voice, the official line is that it’s because they thought the game would be more convincing if the guy doing the mo-cap also provided vocal talents. I dunno. I’d question the wisdom of prizing slightly more accurate lip-sync over one of this series’ most recognisable elements. I’d also say that the newly young Fisher both looks and sounds significantly more generic than previous incarnations of the character. It’s not like Sam Fisher was ever a mould-breaking action hero, but the grizzled aspect at least made him easily identifiable where other game lead characters are not.