The only Twitter meltdowns were from your ilk. Racist Twitter exploded for some reason. It didn't seem like they (or you) even read the paper. At no point do the authors suggest making AI colorblind.
In medicine there is an accepted definition which is used by, for example, the national institutes for health in the US. They use that to define "health disparities" between different racial groups.
That definition is what the researchers used here. Race as a social construct, self-reported by the patient.
Simply testing in multiple external populations already rejects this hypothesis, unless you think they all had the same scanners with the same stuck pixels.
Are you suggesting that this diverse team of leading scientists from the biggest institutes in the world, and all of the famous researchers who have agreed with their message on Twitter etc, have somehow jumped to the wrong conclusion, when you yourself find the answer obvious?
why is this a contradiction? If the radiologist doesn't see the patient, they can't appreciate when the AI might be making decisions based on race rather than clinically relevant info.