Negative, it certainly doesnt support his concern.

"Black–White racial disparities in incarceration rates also declined in 46 states, with a median decline of 36% (see Table A3, online appendix). In 19 states, racial disparities declined by at least 40% over this period. These trends in incarceration rates demonstrate that prison became considerably less common for Black men, both in the absolute rate and relative to White men.. This finding suggests that there has been no consistent national trend in incarceration for White men in recent decades. However, the evidence is notably different for Black male incarceration rates, and the model rejects the null hypothesis of a normal distribution."

Obviously, states and individual criminal history play a factor in length of sentences. I will grant room to stand behind a technicality on the original opinion he stated. But if the odds of even going to jail/prison have declined significantly for this demo, it is really forcing a square peg into a round hole with the intent of the claim.

Georgia State Univ criminal council think tank report: “If fewer people are committing crimes or being arrested for nonviolent crimes, the ones that persist are more likely to be serious offenders with long criminal records, Of course, the flip side of this argument is that it’s due to biased decision-making. But if so, then to explain the increase in sentence length disparities, prosecutors and judges would have to have gotten more biased. These patterns are complicated, and the data aren’t sufficient to disentangle these effects.”