First, 3d artists/modelers aren't people who just digitally recreate designs that already exists. Most of the time they model/design things from scratch. For me a good modeler is a modeler that can model anything that is asked for, with great overall look/design if it's designed from scratch, and high overall shape/dimensions accuracy if we are talking recreation of design that already exist, good/clean/usable topology is minimum. He/she must be able to achieve high results with or without any type of reference. To me it's much bigger challenge to create something from scratch than to recreate something that already exists, because when you design something from scratch there are million things that you have to look for, overall look, design language, will that design fit where it supposed to, how it supposed to. Depending on the usage, will topology/geometry be good/clean enough for 3d printing, will it be good for animation purposes, will it be good performance wise etc. In recreation you don't have to bother with half of those things.