One would be hard pressed to find an episode that didn’t feature Shearer’s vocal talents in some form. A part of the show since its inception in 1989, Shearer voiced some of the more quotable secondary characters on the show, including Ned Flanders, Mr. Burns, Waylon Smithers, Principal Skinner, and countless others.
Considering the tweets mention James L. Brooks’ lawyer, one can assume the split isn’t entirely amicable (it seems to be over contract disputes) and it’ll be interesting to see how the show adapts. In the past, the show has been able to phase some characters out over time but more often than not, Shearer’s characters are the plot drivers for The Simpsons‘ shenanigans. Homer’s plot lines usually involve Flanders or Mr. Burns as the motivation in some form or another and the same goes for Bart and Principal Skinner.
The tragic loss of Phil Hartman in 1998 forced the show to effectively retire his notable characters, Lionel Hutz and Troy McClure. Iconic though they were, they weren’t nearly as vital to the show as Shearer’s vocal creations. It is doubtful the producers will eliminate the characters completely as they are some of the show’s most popular, but this news is certainly problematic, especially considering the series was just picked up for two more seasons. Finding soundalike voice actors seems like the obvious choice, but even with perfect matches there will still most likely be a decline in the prominence of those character’s plots.