Not that much work, really — in fact, Disney streamlined production and often reused material.
Tech is funny. So much work. So many techniques. So many historical breakthroughs. And we end up with a simple "Animate Mickey walking and singing to the right" to a random AI...
https://video.nostr.build/c4e67fb39961540f8261849f9bffda399ce2330f98547976af5ff00b4280c1df.mp4
Discussion
I meant the work to develop those methods. Disney pioneered many of them and in many cases had to develop the tooling for the production runs from scratch.