I think when they said important, they meant distinct or unique. For example, Vin Diesel driving muscle cars is the "important" part of the fast and furious movies, the city/plot/most of the supporting characters are details that could be simplified and reconstructed. An algorithm that generated FF movies could mostly hallucinate silly reasons for Vin Diesel to drive cars and shoot guns, with little real coherency or consistency and I bet the fanbase would love it.