That seems awfully petty and selfish. He's said it was over what he thinks is "heart and soul of the show." His characters aren't objectively that. If he sees so, then that's kinda egotistical. But, I don't think it's over that.
Something I've been misinterpreted as saying, by the way. Now to say it again...
Murray isn't just a character, he's a little side project for Joey. The whole bit about bringing a Muppet outside to communicate with real people instead of a staged, safe studio setting was very much a Jim-esque idea, and I wouldn't be surprised if he took that project as his own little baby. I mean, I'd be proud to call that my own, wouldn't you? I remember him giving an interview for Tough Pigs and letting out a kind of annoyance of the fact that they forced Murray into a street story for establishment purposes when Joey himself stated he wanted Murray to be separate from the main show. He used Traveling Matt as an example, though we all know Matt made some appearances in the Rock, but I get what he meant. Murray was the outside correspondent for the show. So it's much more than "my character's not on anymore" so much as "my special part of the show that I undertook and made a big risk in pitching has been taken away."
Now, how does this factor in on him leaving the show? Well, it only does as far as speculation is concerned. But I never thought
just getting rid of a character was the reason he left. I'd say, and this is the best way to put it, well... okay. Imagine you've got a crappy job where the boss is breathing down your neck, the other employees are either jerks or cold to you, you keep getting in trouble for no reason, you've been turned down for a promotion and raise for a while, and at the very least, someone has repeatedly eaten your lunch out of the fridge. Now, one day things get really bad and while you've been annoyed about your lunch being taken, this time it really set you off. That was the last straw, and you angrily quit. It's not that someone ate your lunch so much as it was one of
many things that ticked you off enough to leave. Now, whatever circumstance for Joey's departure, something tells me he was fighting a
lot behind the scene filming season 46, and I wouldn't be surprised if losing his own contribution to the show was
a reason if not the last straw.
Something tells me he was challenged a
lot of times and I'd say the new SW head and PBS have something to do with it. I'm sure a lot of the changes to come will be apparent when the show finally premieres (I wouldn't be surprised if the re-inclusion of Elmo's World is a sign of things being focused back into the youngest of the demographic again). And they'll be blatantly obvious when 47 rolls around.