The easy answer to this: “fit into a quarter pound lighter short action.”
If the 7RM is great, so must be the 6.8. They aren’t different enough to say one is great and one is worthless. Except 7rm kicks harder, eats more powder, and outruns the Western - as it should - it’s a larger cartridge.
This seems to be the slogan of the insufferable Boomer.
What makes these folks so naive to think anything is a “fad cartridge,”? When a guy can buy brass or ammo online for THOUSANDS of cartridges, drop shipped to their door in a day, not everything new is a “fad.” The 6.5 Creedmoor was a “fad” - but 12yrs later it has taken over as one of the top selling cartridges in the market. The Remington Ultra Magnums were a “fad” but 20yrs later, brass and ammo remain available. Was 375 win ever remotely popular? Why can I buy 38-55 ammo in inventory if it was never actually popular? 6.8 SPC and 6.5 Grendel were a fad, but nearly 20 years later, they’re still being built, ammo made, and both selling well - with offshoot children cartridges for both also in the market. 300blk was a “fad.” The WSM’s and RSAUM’s were a fad, but guys are still building them, and more and more short action magnums hit the shelves every year, world records have been broken with WSM’s in recent years, guys win matches with other short magnums like 6.5 PRC and 7wsm every year still. Naive Boomers likely have never heard of the Sherman cartridges - but they’re being built and sold, and guys are taking game with them with smiles on their faces. Ruger safari magnums like 375 Ruger and 416 Ruger have been very well accepted and are even easy to source upon arrival in Africa if needed.
Maybe fads like Jheri curls, pink sport coats, and perms have faded into oblivion, but there aren’t many cartridges which truly become unsustainable, no matter how many Boomers throw the word “fad” around online.
I don’t have an interest in the Western, and have largely given up on sub-30 cal magnums, but this Boomer crap isn’t cute.
