I'd say give up now and listen to current ones because I think it's strange to relive 2015-2016 via weekly podcasts. There's too much other good, current content out there (and I'm a Simmons fan.)
I haven't noticed any drop in the quality at any time since he move to The Ringer. Some are interesting, some are "Simmons Greatest Hits," and some fall victim to his worst habits (talking over guests, talking to Tate without a mic, pushing his idea without much evidence.) They are what they are but I enjoy them more often than not to at least kill time during work or a commute.
The Theron one was actually a strange one. She was very charming and willing to talk about just about everything but he had no direction for her. He just read down her IMDB, which seemed like a fine idea, but just said the title of the film. He didn't prepare any questions about each one or a theme of any kind. She didn't know how to respond most of the time and called him out on it finally at the end. I'd listen if you're interested in her career at all and, like I said, she handled it well and was charming.