My boyfriend just treated me to a marathon of these the other day. He seems to think they’re the result of a new group of puppeteers/voices–no longer Jim Henson’s son (who supervised the ill-fated late-80s return of the Muppet Show after Henson passed away), but some other ancillary folks who’d been linked to Henson’s original work & decided to try to revive it. I don’t know the whole story.