Again these are not FACTORY OPTIONS!
Carbon fiber barrels and stocks are not factory. You can build a 300PRC on a Remington action but not buy a factory cambered rifle from remington. You cannot buy a Win, Savage ,Browning, Remington or Ruger other than the RPR and buy box factory ammo and shoot it unless single shot or modifications to the mag box.
The RPR is far from your typical Factory gun.
http://lipseys.com/itemfinder.aspx?type=Rifle&caliber=300+PRC
http://lipseys.com/itemfinder.aspx?type=Rifle&caliber=30+Nosler
They are production rifles made and sold by a major manufacturer, how are they not factory rifles?
As much as I love Winchester the current team is several years behind the curve, they just got around to adding the 6.5 Creedmoor to the Model 70. So we might see the PRC in 5 years but they certainly aren't going to introduce the .30 Nosler to compete with the Win Mag.
Savage, Remington and Ruger do not chamber any rifles in .30 nosler and Browning seems to be about 2 years behind the introductions, they offered the .30 Nosler starting in 2018 and the 6.5 PRC in 2019.
You do realize that Christensen offers .300 PRC factory rifles with steel barrels for roughly $1200 but only offers the .30 Nosler in their $2000+ carbon fiber models so by your statements Christensen shouldn't count for the Nosler.
Nosler certainly isn't going to chamber a direct competitor in their own rifles.
In purely factory factory form the .30 nosler is nothing more than a slightly faster Win Mag held to the exact same configuration limitations of a 3.4 Mag and 10 twist. I had to build a custom in .300 win mag to overcome those limitations in 2015 and the .300 PRC factory ammo today is pretty dang close to the handloads I'm making for my Win Mag.
So as I've said before, if you use factory ammo and it's for normal hunting pick the nosler if it's for long range targets/hunting take the PRC and if it's a custom with hand loaded ammo flip a coin.