Well see, the thing about Rowlf wasn't so much that he had an absence because of Jim's death, and trying to find a replacement performer for him, Rowlf had actually been retired out of respect for Jim, and you know, there are a lot of different aspects about Rowlf: yes, he was a key player of the Classic Muppets, but he wasn't exactly that major/pivotal a part of the group, though did have quite a history, as he was the first major Muppet character who was featured on national television back on The Jimmy Dean Show, and all those Purina dog food commercials.
Count on the other hand, he IS vital to the SST cast of Muppets, and Jerry isn't Jim... I don't mean that disrespectfully, Jerry was and is one of the greatest performers the world of puppetry ever produced, but what I'm saying is, Jim Henson was THE visionary behind the Muppets, and he was also the first one we lost (not counting the non-performers such as Don Sahlin), so it was probably a lot tougher to recast his characters than it is recasting anyone else's characters afterwards, whether they're Richard's old characters, Frank's old character, and even Jerry's old characters.
Plus, keep in mind too, these people know they're not invincible, they know that eventually, they have to meet their fate someday as well, so they've been having the foresight to choose who they want to carry on their characters for future generations: Jim chose Steve to take on Kermit if anything ever happened to him, Matt has been Caroll's understudy for Big Bird for a decade now (don't know about Oscar, but I understand Johnny T. has once performed him for something), Frank has been pleased with what Eric has done with his characters, and we know that Jerry has chosen Matt to take on Count after him (and we know he's done a good job thus far with Floyd and Uncle Deadly).
I'm sure Matt may be feeling a little more pressure under these circumstances as opposed to his performances in the new movie, which is why we need to show him support right now, and as I've said many times before, Matt is a great, versatile performer, I was impressed and blown away with how well he did with Jerry's characters in the movie, and I have no doubts that he will do just as good a job with Count; no, it won't be the same (remember folks, we were taught this lesson when Mr. Hooper died), and no, Matt Vogel is not Jerry Nelson, but that doesn't mean he's better or worse, just different, he's just going to need to take the time to take the job and make it Matt Vogel's. Yes, we'll miss Jerry, we knew his time was coming eventually, and we'll always love what he has given us these past generations, but now we'll embrace Matt as he continues to keep the legacy alive that Jerry has now left behind, and I am behind him 100%. All things considered, he has certainly become one of my favorites of the newer performers, and I look forward to him keeping Count alive for all of us.