Because in the US some people have a hard time understanding that all races and genders deserve to be treated equally as humans with the same access to goods and services. Further, that there are disparities in care based on race/ethnicity[1][2] and gender[3][4] because of that racism/sexism present in the systems. This then leads to requiring that race/ethnicity and gender data be scrubbed sometimes to keep people from impacting outcomes based on their own biases.
[1] https://www.americanbar.org/groups/crsj/publications/human_r...
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1924616/
[3] https://www.americashealthrankings.org/learn/reports/2019-se...