My $0.02 ... I get 22.0-24.0 mpg cruising at 70-80mph in flat terrain with no load, measured on the dash by the computer, most often coming at about 22.5 mpg.
2022 1500 RCLB 3.6 3.55:1 limited slip, 87 octane, stock tire size w/ 20" rims, 22k miles, with a tonneau cover.
Headwind/tailwind...