The fastest way to lighten your pack is to leave stuff at home.
Next look carefully at your important big items. Think hard about hour pack, sleeping bag, tent and pad.
I have gotten older so now I carry a tarp, down bag, new fangled light pad, and a ULA pack that weighs under 2.5 pounds. Lighter equipment has kept me out there to age 70. Now I have some heart issues, somy backpacking career may be coming to an end after 60 years.