I got ya Mobuck, the rifle you saw in action. But some of those same enhancements will pick up the game of most any modern cartridge, including the 300 Winchester. OTOH the PRC does have it's own attributes & not just a velocity increase. If you don't have brass or dies for either, there's no downside to the PRC. One might say ammo or case availability, but with the supply chains we've seen the last couple years I wouldn't bet on either.
Yes, rifles costing as much as a decent used truck are readily available, but not necessary. And same for scopes. If ya have the coin, go for it. But thousands of competitors, long range plinkers etc., using much less costly rifles & scopes with good success. With that in mind, it doesn't cost a dime extra to chamber a PRC over a Win Mag, the PRC takes up no more space in the gun & offers the benefit of modern/enhanced case design.
That rifle you mention, must be one heck of a rig.