"Put yourself in the shoes of a highway planner and engineer. Are you going to build a highway through the most expensive real-estate in the region? Or are you going to build it through the least expensive real-estate in the region?"
And so, thousands of black homes and hundreds of black businesses were bulldozed based only on the narrow economic considerations of white highway engineers. That was the central point of the article.
"Systemic racism" doesn't mean that all those engineers were overtly and actively racist (though there's evidence that some of the most renowned, like Robert Moses, were). It means that the white folks in charge made decisions that were blind to the needs and wishes...and subsequent suffering...of the black communities on which their plans had impact.