The Unfair Oximeter?

The pulse oximeter is a cheap device, designed to estimate the amount of oxygen in a person's blood. Studies by NHS England and The Medicines and Healthcare products Regulatory Agency, however, have shown that the oximeter can overestimate blood oxygenation, when used by someone with a dark skin tone (https://www.theguardian.com/society/2021/nov/21/from-oximeters-to-ai-where-bias-in-medical-devices-may-lurk). The pulse oximeter seems to have been devised, with caucasians in mind. A problem arises because the oximeter reading is often used as a 'trigger' to determine which patients need urgent admittance to hospital care in Intensive Care Units. It has even been suggested that 'biased' readings might contribute to the relatively elevated death-rates in people from minority ethnic backgrounds in the UK. Other estimations of blood oxygen concentration could be used but these would involve blood sampling and laboratory tests. The results would emerge more slowly. I wonder if it would be possible to calibrate oximeters for a variety of skin tones?