When a product must be manufactured in bulk before anyone has seen it, the only ideas that survive are the ones a spreadsheet can defend. Range narrows. Everything converges on the safe middle, which is why so much of what is available looks the same.
Made-to-order production changes the constraint. The limit on what can be made is no longer capital committed up front; it is whether the idea is good enough to be worth making at all. That moves the whole burden onto judgement — onto art direction — which is exactly where AVERNOX wants it.
This is not an argument that print-on-demand is automatically better. Made-to-order is only interesting when the thing being made deserves it. Used carelessly it produces the same convergence by another route.