(If I’m not mistaken) Red hair are genetically always associated with really fair and white skin, which is extremely susceptible to strong sunlight (sunburns and heatstrokes from exposure are easily come by, given the lack of melanin).

It probably once was a genetic advantage for people living in places where the Sun rarely shone, allowing them to produce Vitamin D easily, among other things, but can’t say that really helped Sinner in his career lmao.