When you look at history once we went from flint and cap lock front stuffers to a self contained brass cartridge there has been constant development across the world, British, German, Italian, french, Russian, USA etc developed so many different rounds in the black powder through the start of the cordite rounds that they make the current developers look like slackers. They had so many proprietary rounds it make the head spin. What we are seeing is development of very specific focused rounds to meet certain requirement. Hunting, long range target, short range target, military, etc.
I support the idea of development of using all the lessons over the years and using best of breed engineering and develop a good round, bullet, rifle etc. Look at the idea of a MOA or better rifle. from the early 1900's to about 1990's that was the realm of custom rifles or an lucky combo coming from a factory. Fast forward to early 2000's and you can but a factory rifle with a sun MOA with factory ammo for less that $700. The bullets are much better and the current factory match ammo takes some work to better.
I always say lay out your requirements and capabilities of yourself and equipment. I enjoy shooting my 6.5 creedmore, have hunted with it but to me it is a deer/impala and smaller kritter round. Does it do anything that a 6.5x55 does? Nope but factory ammo availability the 6.5 Creedmor has the advantage.
Where things went south is when the writers and internet folks declared it the best thing since sliced bread and that it was good up to moose. Shoot the appropriate Premium grade bullet/rifle combo for the game to be hunted and don't go hunting with the "It can do it if everything is perfect mentality" The folks that do that tend to get visited by Mr Murphy very often.
For me I will choose the right round in my mind for my hunt. My favorite hunting rounds fit in an older rounds in very accurate rifles. 7x57, 7x64, 300 H&H, 9.3x62, 375 H&H, 404 Jeffery, 505 Gibbs in bolt guns. 22 hornet,,7x65r, 9.3x74, 450/400, 500 NE, 577 NE in doubles or single shots
I shoot 6.5 creed, and working on 300 PRC for punching paper and ringing steel. Also will hunt deer/impala and below with the creed and the 300 for elk/kudu and smaller if that is the rifle I decide to take.
The manufacturers and the spin doctors will constantly try and reinvent the wheel and make it look like the best ever, but that is their jobs of making a profit and following the current trends. Our job is to select the appropriate round for the hunt we have in mind. We owe it to the animals to cleanly harvest them.