I think the big thing is that hub and spoke was always considered more efficient but here they are saying that if you take into account resilience into the equation then p2p may be more efficient than a hub and spoke model.
Hub flying is useful for folks that want to go from one small city to another; on a given day there might be two people who want to fly from Providence, RI to San Antonio, TX so it's not viable to fly a plane between them, but if you route them via Philadelphia, PVD-PHL-SAT, you can accommodate them with limited extra distance or extra time and also accommodate people wanting to travel PVD-PHL and PVD-PHL-SYR, etc.
Once you start working in units of "planeloads" instead of "people", point-to-point flying is likely going to be more efficient in terms of time, distance, cost, etc...