Otto Bock designed the largest caliber round one could stuff 5 down in a standard M98.
The bullets have also been good, for the velocity one where getting..
It was the most and widest used big game caliber in Africa for decades.. few complaints it seems.

The 375H&H needed a Magnum action.. making everything more expensive and heavier. You know.. exclusive and expensive.
Its also a waste of space.. when you have a Magnum action, you step up in bore, not speed.

9,3x62 = 308
375H&H = 300WM

Yeah.. it got a bigger boiler room.. but not really needed.
Unless you constantly shoot big game at 3-400m.