If you look at Femke Bol's 800m potential, her being 6' 143 lbs jumps out at you. She doesn't look super tall and she looks very thin. That is a good height and weight for a middle distance runner. However, Athing Mu, though, is listed at 5'10" 124 lbs! That is thin. Another thing, Bol did not show remarkable speed as a teen and still hasn't run a sub-23 200m. At 18, she still sported bests of only 25s 200m and 54s 400m! For years she was stuck near those numbers. The speed decay is still very good, because she has pr's now of just 23 for 200m and 49.44 for 400m, which is very good. However, there again Athing Mu looks even better for speed decay. She ran 23.5 already at 16, but her pr is still slower than Bol's at 200m. At 400m, her pr is still slightly slower than Bol's at 49.57 but her relay split in the Olympics in 2021 was 48.xx, so I see her 400m ability as still significantly better. Then at 1500m, Mu ran 4:16 and was going a lot faster before running out of steam at 1200 or whatever last year, so she has a big aerobic edge over Bol.