This is simply their (Wilson Combat's) "Me Too" .300/.223 caliber/case conversion that fits an AR platform. Nothing more.
The .300 / .223 conversions really took off with the .300 Whisper. That brings 7.62x39 performance to the AR platform. Shines best when suppressed! However as you probably know they did the "licensing suicide" trick and it remained a niche catridge.
The .300 Blackout followed the same case design (.30 bullet + .223 brass) but chose to make their case design "free" and suddenly everyone is freaking out for this .30 cal conversion since it requires ONLY the new barrel. In fact the Blackout is so close to the Whisper design that it lets you shoot Whisper brass if you have it.
It seems that everyone must have a .300 Whisper/Blackout/UberZombie case design for their sweetheart AR platform. To be honest the Blackout seems to be the way to go. I simply can't see adopting an offshoot design that is so close in performance that you would just be better to go with "mainstream" stuff where reloading supplies and now even factory ammo is abundant and seems to be here to stay. No special size bullets, just plain 'ol .308 bullets and you're set. That alone is a HUGE win for this cartridge and will most likely ensure that the 6.8 remains a niche caliber.