If the unwashed masses (ie. us civvies) can only get watered-down brass stuff I don't see it really catching on. You seem to need to load it to hand grenade pressures to the touted performance. And while metallurgy improves yearly I can't help but think you'll get < 2,000 accurate rounds out of a barrel, maybe a lot less. On top of that I don't believe the claims of performance against body armor. The mil is saying it defeats "all known armor" and anything they can foresee which I expect is already not true, or will be very soon. The arms race between offense and defense has been going on for a few thousand years and never seems to settle long. My suspicion is that the Adept Colossus RF3+ might stop it, and in any even once the ink is dry on the purchase order someone will develop armor designed to stop it. Maybe most folks won't care but that was ostensibly one of the main excuses/reasons for a new round, to face near-peers in body armor. And unless the NFA is repealed I don't think everyone will warm up to shooting this beast unsuppressed. Obviously this is just my guess. As has been mentioned whatever the mil gets usually is coveted by the civilian market but this feels like a niche round. We'll see if even supplants the 5.56 for general military use.
