As a 25+ year NPR junkie, I can say Gross brought on the trend of hosts thanking their guests "so much" for being there. This started somewhere around 2011.
I used to believe Gross was the best interviewer until I heard some Stern interviews from 2014. While Stern talks a lot more, he is able to elicit more genuine responses from the guests and his interviews are real-time, not edited. Fresh Air suffers from having to break every 10 minutes.
I believe the parent was referring to Gross's recent two part interview with Stern. It's actually reveletory to hear them discuss interview technique (for example, interviewees are physically present with Stern and are not with Gross) although it's not a major part of the interview.
One observation: Stern was not always as effective an interviewer as he has been in recent years.
I used to believe Gross was the best interviewer until I heard some Stern interviews from 2014. While Stern talks a lot more, he is able to elicit more genuine responses from the guests and his interviews are real-time, not edited. Fresh Air suffers from having to break every 10 minutes.