Not even just genetically, people become acclimatized over time. We see this when less hot locations experience heatwaves, even when the temperatures remain below what hotter locations experience routinely, the rates of heat stroke still rise, which isn't ethnically disparite.

The ridiculous part of this argument is that your medical records will already take this into consideration. If your clinician doesn't consider your anatomy, while still respecting your gender, they are bad clinicians. This is just an argument someone makes if they are either not a healthcare professional or they are just being disingenuous.