A white cop murdered George Floyd. He will answer for that crime.
In Jim Crow America, white cops, white lynch mobs, and white domestic terrorist groups (which the KKK were) regularly lynched black people and got away with it. Indeed, the KKK and their sympathizers introduced the notion of gun control to America (previously unthinkable due to the Bill of Rights) with the "black codes" for that purpose: it's no fun lynching people when they're shooting at you.
Like it or not, most black violent deaths these days are at the hands of other blacks. It's not racism, it's a toxic culture. And yes, white racism is partly to blame for it: decades of slavery and a century of Jim Crow did help form that culture. But comparing the isolated racism of today to the institutional racism of yesterday is ridiculous.