Since it's highly likely someone is going to ask, here's some information on how Keenan creates the beautiful illustrations in papers:
https://www.cs.cmu.edu/~kmcrane/Projects/Other/IllustratingG...
https://www.cs.cmu.edu/~kmcrane/Projects/Other/IllustratingG...
For example, a recent paper of his team "Repulsive Surfaces" is on arXiv, where the source files of the preprint PDF are available for download
The inset figures are probably placed using the “wrapfigure” LaTeX package. It’s janky and frustrating to use, but I agree the results look great!
EDIT: Incidentally the template changed recently and people within the graphics community complained about some aspects of it, e.g. the equation typesetting and how subsections and lists are formatted. It's good to hear that people outside the community like it.