Cookie and Grover are still very much active members of the show, and both still have their own segments. Cookie even has a new segment, replacing the Crumby Pictures series with Cookie as a spy working with sentient cookies.
It's the likes of Telly that are getting far less screen time.
As it stands, Murray was the only major one of Joey's characters. While he always performed quite a few bit parts, the show's giving less focus on bit characters and a more focused set of the most marketable. Besides, the block format has been toned down at least to the extent of no longer having the Murray hosting blocks (half hour format, you see). Murray seems like he would have been completely phased out, except for some reruns of Murray has a Little lamb used this season.