There may be several thoughts on this post, so apologies up front.
Ok, whether it's shooting people or animals, it's about shot placement.
It's also a bit about evolution. Animals have been prey for millennium. Man has been been a predator for a bit less. So, when we hit an animal with a projectile, the response is different that when striking a human. Instincts kick in, and almost always, the animals instincts are to run. Be it pain threshold, shock, will to survive, it's just nature.
This proposal has been active for some time. I believe the original proposal was for a .30 cal projectile at that same velocity. Some friends developed a round/firearm for the selection. It was a 35 Remington, necked down to .30 cal. It was fast and accurate. They named it the 300 Viper. They submitted it for SAAMI , but don't know what ever happened. Obviously didn't make the cut.
We, and most of the world used to use .30 cal projectiles in all our rifles, but at some point, (can't honestly recall when, but not that long ago), decided it was better to carry more ammo, and actually wound our opponent than to kill him. This had several benefits. It caused psychological impacts on his fellow soldiers, required at least 3 people to evacuate him, and put a strain on the medical/logistical support. Dead soldiers require a hole, wounded soldiers require care, and potentially lots of it.
Then there are the actual number of soldiers who fire their weapons in combat, and at the enemy. Read the books by RET LTC Dave Grossman. He gives great insight into what occurs in a firefight, going back over 100 years.
We all want our soldiers to be solid in a firefight, but the facts simply don't support it. The actual number of troops who engage is suprisingly low. We also have policies where when in contact, the first call is for either air support or artillery (where possible). The last thing nations want is to see their sons killed, and posted on social media.
So, it sounds like a decent round. Will the top troops adopt it, probably not, because they actually hit what the aim at, and actually shoot. Maybe in the GPMG, but we will see. Will it become the standard issue for infantry, maybe, again, wait and see.