The lightest scoped & slinged .375 H&H R8 configuration is 4,282 grams, or 9 lbs. 7 oz. This involves alloy receiver with polymer trigger group, standard 17 mm 25.6" barrel, no kickstop, and typical 30 mm 1-6x24 scope. Many like it that way
I personally find that the "12 oz." kickstop balances the rifle very well, to the point that I have one in my .223 configuration. This is certainly not for recoil, but for balance, and I really do not mind the additional 10 oz. (mine does not weight at quite 12 oz.).
With the .375 standard barrel this makes the rifle just an ounce over 10 lbs., which has always been the benchmark for a .375 in the good old days, with reason I believe.
Sure, we carry a lot more than we shoot, but a bit of heft really stabilizes the rifle in field positions, and some uncertain field positions have a way to turn into a scope bite all too easily
My own preferred .375 R8 configuration involves a steel receiver, a steel trigger group, and a semi weight barrel. Sure, it makes the rifle weigh in at 11 lbs. but it is so easy to shoot that I group the .350 gr .375 slugs at max load within a sub inch cloverleaf, and since I cannot tell if I have 9, 10 or 11 lbs. slung on my shoulder, it really works for me
Besides, carrying an 11 lbs. double rifle 12 hours per day, days on end, while tracking elephant is considered perfectly fine, so I kind of miss the point why carrying a 10 lbs. or 11 lbs. .375 would be bad