This is based on information posted in his manifesto. He also sided with the Ukrainian nazi Azov battalion. There are pictures online confirming this From the manifesto: (He is) “in the mild-moderate authoritarian left category.” The media are attempting to spin the narrative.
These random events don't have much deeper meaning one way or another. It is very unusual for a mass shooter to target blacks, but sometimes it happens. One summer night in Chicago will kill more blacks.