That's how human brains work. People have an intrinsic need to sort, build hierarchies and prioritize. Effort spent is one of viable heuristics for these processes.
> Why should being an artist be a viable job?
Art itself has great value, if it weren't, museums, theaters and live shows wouldn't exist.
> Would you be against technology that makes medical doctors obsolete?
The analogy doesn't work. The results of a medical process is a [more] healthy person. The result doesn't have any links to the one performing it. Result of an artistic creative process is an art piece, and art is tied to its creator by definition.