Boris Gudenuf
Deity
. . . Ultimately, if Civ6's leaders truly are the single most time-consuming element of the game, it's not because they couldn't be done faster. The lead developers simply agreed the game will never need to have that many of them and they can thus take their sweet time (it's honestly not even *that* slow, the initial waves of DLC gave the game 18 leaders in a span of 15 months including 2 holiday seasons and all the surrounding scenario and R&F work).
Now, here I think we are agreed: the animated Leaders are in fact totally unnecessary to the game: they are a marketing device, a "nice to have" feature but have no bearing on the play of the game itself. The 'Uniques' attached to the Leaders are there whether they are completely animated portrayals or still cartoons. That means, whatever resources of whatever kinds are available to the game design team, there are better places to use any of them to make a better game than on an animated, articulate, linguistically complex Leader.
And, @sukritact, your comments in a way reinforce my thoughts on this: they could get a lot more 'bang for their buck' by allocating more of the resources to better and more variety of Unit animations, terrain/map, buildings, wonders and Improvement graphics and animations. As an example already commented on elsewhere, Humankind's herds of deer and occasional elephant wandering the landscape - no apparent effect on game play, but much more visible as a graphic Bonus as you play the game than an intermittent Leader Board.