New voice actor for Dr. Hibbert
It seems a different voice actor has assumed the role of Dr. Hibbert. His voice and, especially, trademark laugh are noticeably different now. I think it would have been better if the show runners had retired the Hibbert character and created a new character to replace him — voiced by a minority voice actor if that is deemed necessary to achieve social justice — or had Dr. Nick take over.
It’s dumb to require that animated characters need be voiced by voice actors of the same race/ethnicity. If one follows the dumb logic of cultural appropriation, for instance, only African actors should voice the animals in Disney’s Lion King rather than black Americans. Avoiding racial stereotypes in the characterization of characters of racial or ethnic groups is a separate matter. It should either be avoided or the show should strive to be an equal-opportunity offender.