My Pixel 8 cell phone just got some updates, and upon restarting, the Call Screen feature was no longer present in the Google Phone app’s settings. I tried lots of recommended stuff, but this finally did it (via https://support.google.com/pixelphone/thread/239097234?hl=en&msgid=246915696 … thanks, kevinmbradley!)
1. Go to Google Play and find the phone app "Phone by Google".
2. Click "Uninstall", which for most Android phones will just remove all updates.
3. Open the phone app to be sure the older version is installed.
4. Go back into Google Play, find the app again, and click "Update".