Class segregation isn't the same thing as racism.
It seems clear to me given the evidence presented, that bias in the justice system does not account for the gap when it comes to serious crimes. Given this, in my opinion "Blacks commit crimes at around 5x higher rate than Whites" is a fair claim. I actually should have said 8x, I misremembered the article.
One interesting thing to me is that within parts of academia, it is not controversial to claim that Black people commit more crimes. Such academics seek the causes of this difference in various sociological explanations. You can see the discussion in the rest of the wiki article. But outside of academia a very different story is told. I believe that academics think that ordinary people cannot be trusted not to draw "racist" conclusions from the statistics about crime. Therefore liberal academics do nothing to dispel the myth amongst mainstream liberals, that Black crime rates are mainly due to bias in the justice system.
His concern seems to be that your stated source focuses on "offending" which implicitly infers that they are caught and charged by law enforcement.
Your assertion was about "commit[ing] crimes" while your fact is about "offending" or charged or convicted with crimes.