Threatening their business model is overstating it a bit I think. More like they had already successfully picked all the low hanging fruit and in order to maint

Threatening their business model is overstating it a bit I think. More like they had already successfully picked all the low hanging fruit and in order to maintain their stellar (multi) year-on-year passenger growth they needed to start trying other things (customer experience improvement, more focus on business flyers, serving more primary airports, dipping their toes in to offering a few connecting flights). Short-haul LCC traffic in Europe is becoming a mature market and so budget airlines are on a drive to find ways to grow beyond simply offering "insanely cheap prices". However, it's important to remember that a bad/hostile customer experience didn't stop Ryanair getting to ~100 million passengers a year (note: not that I'm defending that!).