Those amazing bullets you love so much... that is the whole point of the catridges

. The ctridges are designed around those bullets and optimizing their performance with better catridge geometry, tighter tolerances, mor consistent headspacing. Nothing wrong woth the 06 unless you need the performance or shoot better with lower recoil or you like efficiency and better ammo selection. Many of the old catridges you site are incompatible with the highest performing bullets. 300 win out side of reloading is incompatible with the bullets the 300 prc were designed around.
This whole argument is equivalent of saying all you need is a 57 chevy the latest line of trucks is all marketing.
That statement can be true for an individual but marketing is not the reason for new catridges. Military and competition world drive new catridge development and the design of a catridge can have huge impacts on performance. The 30-06 has no place in the military or competition world... Just like the 57 chevy it will still get you from point A to point B but let's not blow so much smoke up our asses...
Sincerely,
The Fudd Patrol