Why does it matter that he's Black or an Elizabeth Warren supporter? Did he kill people because he was an Elizabeth Warren supporter? Did he kill people because he was Black?
That's what White Nationalists do (and why it's note-worthy that they're White Nationalists). White Nationalists kill people because they're White Nationalists, which basically means that they're terrified that their tiny little white dicks are going to become a joke in the brave new world of multiculturalism and so they kill people that represent and/or support multiculturalism. They usually leave some idiotic psychotic poorly informed and poorly written manifestos behind for other knuckle dragging idiots to read.
It looks like this guy killed people because of mental illness and/or possibly a personal dispute at work (although that's largely based on reporting from the New York Post, so who knows). My guess is that's why nobody's talking about it. Because nobody knows why this guy did what he did yet.
The fact that you don't see a difference says a lot about you, and absolutely nothing about anybody else.