For a long time, people have also guessed that Mac is the device that introduced Face ID after iPhone and iPad. In fact, the Mac has not joined Face ID for a long time. The hardware is also a reason. Although the MacBook is also equipped with a FaceTime HD lens, it is completely different from the TrueDepth lens used by Face ID. The biggest difference lies in accuracy.
9to5Mac found some code from macOS Big Sur Beta 3. It may predict that Big Sur will add Face ID support. Some people found something named "PealCamera" in the code of Beta 3, maybe many people didn't realize it, but this is exactly the Codename in Apple's iPhone X Face ID.
In addition, the code in Big Sur Beta 3 also appears with words such as FaceDetect and BioCapture, which is obviously related to Face ID. And this is not something related to Catalyst, but an Extension for macOS.
Reasons why you cannot use FaceID on x86
In addition to the TrueDepth lens assembly, FaceID now needs the Neural Engine inside the A-series processors to be used together. The reason is that FaceID will use Neural Engine for mechanical learning to continuously improve the accuracy of FaceID. Therefore, this may be one of the reasons why the current x86 processor MacBook cannot implement FaceID.
Born for ARM version of Mac
Although there is evidence of Face ID from Big Sur Beta 3, even if Face ID is introduced to macOS, it is believed that it can only be used on a MacBook equipped with a new TrueDepth lens. Currently, all MacBooks do not have this component, only Touch ID. It is unknown whether this function will be added to the ARM version of MacBook launched at the end of this year.