According to multiple Samsung Galaxy owners, the Trusted Devices option is no longer available on their devices and is missing. This is also true for Google Pixel owners. Trusted Devices is a feature that keeps your phone unlocked when it is connected to a Bluetooth watch or a car.
Trusted devices is a part of the Smart Lock feature on Android 13. Google renamed it as Extend Unlock on Android 14. However, many Samsung Galaxy and Google Pixel owners have reported that they are only seeing the On-body detection and Trusted places options in Smart Lock/Extend Unlock.
The Trusted Devices option on Google Pixel phones went missing after the Android 14 QPR1 Beta 1 update. However, the feature is also missing from Samsung Galaxy devices, including the Galaxy Z Fold 4 running Android 13 and 14 on Google Play Services v23.35.15. Do note that the feature is still available on some phones, but there is no clarity on why others are missing the Trusted devices option.
Looking at the reports, it seems to be a bug with the Extend Unlock that has plagued multiple Samsung Galaxy and Google Pixel devices. In the past as well, one of the Smart Lock options disappeared away. Previously, for many users, the Trusted ppaces feature went missing from the Smart Lock, which was fixed after updating Google Play Services. If that is the case, then an update to the Google Play Services could resolve this issue.