In this chicken or egg scenario, it would appear that Reliable Sources might have been canceled first, which is why Brian Stelter is also leaving CNN. In June 2022, the New York Post reported that the show saw its lowest ratings since 2019.

“Stelter’s show logged just 580,000 last Sunday [June 12], and a mere 73,000 viewers in the all-important 25-to-54-year-old demographic, Fox News reported. The show lost 13 percent of the total audience and it marked Stelter’s smallest audience since Sept. 15, 2019.”

Source: https://www.distractify.com/p/was-brian-stelter-fired-from-cnn