Firaxis didn’t “cheap out” on leader VA
A lot of people have complained about the amount of VA in the game, both from leaders and from the narrator. I see this expressed as saying that Firaxis cut corners or cheaped out when they had to pay voice actors. Compared to Civ VI though, there really isn’t a difference in the number of voiced lines. Each leader in VI had seven voiced lines: approval and disapproval, (when they would randomly drop in to praise or insult you) attacked, declares war, defeated, greeting, and a “Civilopedia quote” that I have to imagine most players never even heard.
Civ VII leaders also have seven voiced lines each: a greeting, attacked, declares war, defeated, the quote they say when selected on the new game screen (essentially replacing the Civilopedia quote), accepting a peace deal, and rejecting a peace deal.
The “problem” is actually in the last two. Accepting a peace deal will not happen with all leaders you encounter, as it’s likely you won’t go to war with most leaders on your map, or just exterminate them without a deal. And the REJECTING a deal line will almost never be heard at all. Since the game tells you on the peace deal screen whether the leader will accept or reject a deal, you have no reason to propose a deal they’re going to reject (unless you want to hear the line of course).
In conclusion, if Firaxis just put the accept and reject voiced lines when leaders respond to your diplo agreements, we’d hear all the lines more often and feel like the game was more fully voiced. On the other hand the agreements happen so often they might get annoying.
PS: in Civ V leaders actually had a ton of lines, including little remarks and greetings that would vary based on their tone and attitude towards you, but Civ V leaders were notoriously complex in art and production design to the point where they were said to be limiting production. Civ VI and VII are equal in number of voiced lines per the Wiki