The issue reported here-in is reproducible at-will every single time.

After the last Windows 11 23H2 update, the Dell camera driver for IR\Windows Hello\Presence Detection in Dell Optimizer no longer functions. This is caused by an incompatible\non-functional Dell IR camera driver.

In the image below, "Presence Detection" does not appear in Dell Optimizer because the Dell IR camera driver no longer functions\cannot start the IR camera.