And the invention of the keyboard is linked to online bullying.

There is a point in which the relation is so far-fetched and non-causal that it doesn't make any sense to mention it, and the link between evolution denial and white supremacy absolutely crosses that line.

White supremacy is also linked to the sun rising up each morning, detergent and open borders. None of them relevant.

Both can be causes of an underlying problem, not necessarily origin and consequence.

Is not a surprise that stupid people is generally stupid in more than one field. Somebody believing white supremacy has a previous mental condition that makes him/her blind to obvious contradictions in that speech. Thus, will be probably less capable to grasp complex concepts like evolution (or will choose to ignore it by a different motivation, like greed).

I'll give you the link I gave the other: https://psycnet.apa.org/doiLanding?doi=10.1037%2Fpspi0000391

This is a large meta-study finding a link between white supremacy and disbelief in evolution.

The link isn't hard to see either, white supremacists are primarily found in qanon and other right wing conspiracy bubbles. They are more susceptible to believe in bullshit than tolerant people, like creationism.