I don’t think the angle matters as much because the distance is based on a specific body position and the ability to apply power through the touch points. its a bit fit metric not a bike design metric.
It’s based on the grips so it takes stem length and all that into it. The distance and its meaningful value is based on the ability to completely open your hips while not bending your arms to be able to put full power into the bike. Like an Olympic lift.
What's everyone's opinion on Lee McCormack's "Rider Area Distance" sizing? Basically the distance from the BB to the center of the grips needs to be no longer than the height of your hands standing straight up (deadlift bar height).