Not true! Serling wrote more than a third of the scripts for the show—35 out of 98, to be precise. While he chose to take a less active role than he did on The Twilight Zone, he created the concept and his story material and scripts defined the direction of the show. Serling was deeply involved in these important aspects, and that shouldn’t be dismissed.
And Serling did make a great host. He wrote the intros for all of the segments that he introduced, and his screen presence left an indelible impression.