Google has confirmed that its five years of software support for the Pixel 6 series does not cover all software for the devices. Unfortunately, Google can only guarantee five years of security patch updates, with three major OS updates coming the way of the Pixel 6 and Pixel 6 Pro too.
https://www.notebookcheck.net/Google-s-five-years-of-software-support-for-the-Pixel-6-and-Pixel-6-has-a-relatively-large-caveat.574832.0.html