I would argue that the ultimate quality would be achieved by both working together.
As a programmer I can produce utterly convincing interactive simulations of very boring scenes.
I'm sure a good artist could produce much more interesting scenes, but without the help of software won't be able to make those interactive.
Until the two work together I don't think you get really great interactive scenes.
Artists can make detailed models, but it takes a good engine to manipulate them and apply LOD techniques to make them appear without aliasing. An artist could come up with the perfect look they want for a specific scene, but if it needs to be dynamically generated it might take a programmer to understand it and write an algorithm to generate it.