According to reports, Google has delayed the Pixel Watch internally because of chip shortages. Allegedly, the company may still unveil the Pixel Watch next week with the Pixel 6 and Pixel 6 Pro, which should mark the appearance of Wear OS 3, too.
https://www.notebookcheck.net/Pixel-Watch-Google-may-still-announce-its-first-smartwatch-on-October-19-but-do-not-expect-a-release-anytime-soon.571298.0.html