Author here. I'm happy to answer any questions although this project was from 10+ years ago so I could be a little rusty.

Over the years I've been trying to find better ways to do this kind of visualization but for other CS topics. Moving to video is the most realistic option but using something like After Effects takes A LOT of time and energy for long-form visualizations. It also doesn't produce a readable output file format that could be shared, diff'd, & tweaked.

I spent some time on a project recently to build out an SVG-based video generation tool that can use a sidecar file for defining animations. It's still a work in progress but hopefully I can get it to a place where making this style of visualizations isn't so time intensive.