That accusation has come up before. In fact, there was a recent episode of The Simpsons calling this out. And other shows have also alluded to the idea that "authors" are just "faces" for mass-production writing sweatshops.

Considering that this is how most of the surviving newspaper cartoons have been done since at least the 1970s, this shouldn't be unthinkable. (think Hi and Lois and Beetle Bailey, the guys who created those strips pretty much invented the factory-line comic strip, iirc.)