From the article, it sounds like it's roughly half that on the Pixel 7 at least, around 7-8Gb, since they use an A/B os partition scheme to make OS updates work better.
Actual android takes about 800MiB, judging from the lineagos flashable zip files.
>What the hell are they putting in there?!
Several ISOs of Call of Duty: MW2 and a BluRay-rip of Jingle All the Way.