Phoronix reports that the move will "benefit their latest Intel Core 13th Gen 'Raptor Lake' wares and prior generation devices."
Intel ME is disabled for their latest Raptor Lake laptops and most older platforms, with some exceptions, like having a silicon issue with Tiger Lake.
System76 has also added a new firmware setup menu option for enabling/disabling UEFI Secure Boot. The motivation for making it easier to toggle Secure Boot is to allow Windows 11 support with SB active while running System76 Open Firmware.
The outfit said that it had also resolved a core boot bug that allows the Intel ME (Management Engine) to be once again disabled."