I've felt for a long time that Kermit was getting increasingly marginalized in post-Henson Muppet productions. The emphasis in the movies and specials over the past couple of decades has been shifting increasingly away from the core of Kermit, Fozzie, and Piggy and more toward the favorite characters of the current lead Muppet performers -- Gonzo (Dave Goelz), Rizzo (Steve Whitmire), and that irritating prawn Pepe (Bill Barretta)
That's a pretty hilarious criticism of The Muppets, considering Gonzo had maybe a dozen lines in the film, Rizzo was only seen (and not heard, at all) in two shots and Pepe had one scene.