We don't care how old we are, or about how poor the show has gotten, or even that we don't really watch it anymore. We're not ready to let go of the characters that Harry Shearer voiced, not now, not ever.
So for our own mental well being, if The Simpsons could just go ahead and give his old job to Brock Baker, that'd be swell.
Baker, a Los Angeles voice actor, has a great range of Shearer's characters in his repertoire, as he shows in this video. And although nobody could ever compare to Shearer, he definitely makes a fair stab at it.