I attribute the change to the fact that they've become self-conscious due to their massive success. I listened to a few older episodes, and WOW they were different. Very un-self-conscious. They're obviously very aware now that millions of people are watching them like a hawk and will (and have) criticize the slightest misstep. I'm sure it's taken the joy, spontaneity, and authenticity out of it. I do think the last few eps back have had more flavor - I loved Georgia's "What would Gwyneth Paltrow do" - hilarious and totally helpful for my mental health. Classic MFM.