100%, I used to joke the reason for this is its the "nobody got fired for buying IBM" color system.
#1 it takes the most modern widely accepted space in color science, CAM16 for hue and colorfulness. CAM16 is relatively incredibly complex, about 500 lines of code.
#2 it maps it to L*.
#1 is because nobody gets fired for basing Google's color system on CAM16.
#2 is for WCAG.
There was continually interesting conversations on what exactly the name of the space was and whether it represented a new color space that precluded more formalization of it, the code ended up being the spec as it were. I did get a blog post out: https://material.io/blog/science-of-color-design
Looking at the code, it seems the computations are much more involved than OkLab, especially in the HCT -> RGB direction?