"And we KNOW just how many miles are chopped off your day per pound weight extra. See Ryan's article on the [Arctic 1000] trip, where he spells the numbers out clearly."
True if you are operating day after day at the limits of your physical abilities. But for many, a day of hiking is well below that, with the extent limited by smelling the roses, photography, daylight, etc.
Your days May be enjoyable with less weight, but the tipping point will vary, depending on strength and ambition.