Great cartridge, but will likely be a minimal cult following. Nice choice for moose and bears, especially in a light rifle.
Partially to blame is the fan following of both 300s and 338s. The major producers are US based, and US shooters like these two calibre selections.
Also, although I can't speak for all WW2 Vets, but my father hated the 8mm simply because it was the Enemy's weapon. Based on what I saw from my family history, I would wager that many of the older US, Brit, and Canadian boys carried a similar bias. Yes, it was a whole different cartridge, but that dislike gave the calibre a negative aura for some.
I think the major stumbling block was much of it's initial press. I remember several articles referring to the cartridge as the ideal mule deer round, making the crowd of 243 through 300 fans say, "WTF?". Although it is now chambered in several rifles, much of the initial hype centered on a Nosler 48
rifle; not exactly affordable by every hunter. Compare this to it's 270 and 300 brethren which were marketed to 'Average Joe' and offered in affordable rifles from Remington, Winchester, Weatherby, and Savage.