Hardly. Hunters took elephant for years with the .577 and .600 cartridges of the black powder era, with both preferred frontal and sometimes necessary flank shots. Usually double rifles were preferred, as recoil was brutal, and reloading could be problematic with several tons of very mad animal coming your way at full speed. And even as nitrocellouse powder came into use and improved nitro-powder loads for the big doubles challenged the smaller calibers that became viable for the same purpose, there were adherents of either approach- and those who happily tried both.
But hunters of that era rarely worked alone, and you gauged the character of your friends as if your life depended on them, because it very well could.
There were even those as late as the 1960s and '70s who found the big double rifles just the ticket, such as those of the Rhodesian .577 Society and the Terre Haute Torque and Recoil Society. But they hurt my ears. And shoulder.
But hunters of that era rarely worked alone, and you gauged the character of your friends as if your life depended on them, because it very well could.
I think it was once said that companion hunters of the highest possible skill and courage were required to hunt BUFF and that selection for such a hunt was a compliment of the highest order. BUFF and HIPPO kill more folks each year than just about another other species.
I remember the reload sequence for a double rifle was to have the spare rounds held between the 1st and 2nd & 2nd and third fingers of the off hand for quick insertion into the chambers. Is that correct?