Here is the use case I got from AMT team.
“MEI driver enables communication from OS and userspace to firmware. This will enable OS based device management agent to configure/reconfigure AMT firmware. Which also means management console could coordinate/orchestrate both in-band and out of band manageability simultaneously. “
It doesn’t seem to be enabled by default on KBL. If you can briefly explain the usecase (secure remote control?) and how this MEI driver will be used in your case, it will help.