Adding Timo explicitly who said in https://bugs.launchpad.net/ubuntu/+source/linux-firmware/+bug/1624164/comments/5 that kbl_dmc is optional and for power saving, but skl_guc_ver6 is actually needed on Skylake. Skylake devices are what we have and which don't properly work without the firmware.
Adding Timo explicitly who said in https:/ /bugs.launchpad .net/ubuntu/ +source/ linux-firmware/ +bug/1624164/ comments/ 5 that kbl_dmc is optional and for power saving, but skl_guc_ver6 is actually needed on Skylake. Skylake devices are what we have and which don't properly work without the firmware.