It appears that not many people know what goes into animating and rendering these scenes.
One finger movement, blink of an eye, turn of the head, "awkwardly bump" a little more realistically, can take an entire day just to animate, and over night just to re-render 30 seconds.
Also, if the artist is under pressure (as they always are) and are bouncing around with mouse and keyboard shortcuts that you have to use in Blender... and just one value out of the 2000+ scattered across properties gets mangled/changed... it's a week or longer just to find the problem.
The bottleneck and biggest PITA is the software. Not because the artists want to screw anyone. They would love to finish ASAP to get to the next fantasy, just as much as everyone else wants a quality 5+ minute fappable video.
NOTE: I've been seriously studying Blender and alternatives over the last few months, wanting to begin bringing some of my characters to life. I killed that insane idea until there's some improvements in the software. It's a mess, and i think you either have to be insane to do it, or go insane once you do. IMHO.