It took year for rifle rounds such as the 25/06 and 35 Whelen to be legitimized
you must admit that both of those rounds are excellent rounds, and important additions to the available cartridges.
If either of them had nothing new to contribute, I'd agree, but the 25-06 and the whelen both were very superior to available rounds in those calibers.
I agree that the 8mm magnum basically just filled a hole in the caliber charts between 300 and 338 magnums, and any real added value over either of those rounds was pretty small.