We are looking for people to make 90+, 92+ if reasonably healthy. 75 is super low, and apart from exceptions is a _very_ concerning value. See the dissociation

We are looking for people to make 90+, 92+ if reasonably healthy. 75 is super low, and apart from exceptions is a _very_ concerning value. See the dissociation curve of hemoglobin/O2 to know why. However yes, in my experience I never had enough difference in dark-skinned individuals to be clinically meaningful.