Let me try this from one other point of view, and before I say anything let me state I love my double rifle in 7x65R and 9.3x74R. BUT you have to consider the weight of these rifles, dragging them through the woods. Today with the advent of Mountain rifles and Stalking rifles and the manufacturers trying to lighten the load. Why hunt whitetail or any other animal dragging an extra 3 to 5 pounds around?
I recently hunted boar with my 470. I loved it and I had more fun than you could imagine. But at the end of the day my ass was dragging carrying around that gun. I would do it again in a minute but it needs consideration when trekking through the mountains. The double rifle owners here are a breed of gun lovers and do it for the love of it. Manufacturers have to think about the rest of the world.
Just my observation and humble opinion.