What you mean is they don't do connections
No, that isn't really what I mean.
What I mean is that EasyJet is not competing with legacy carriers in terms of the business model. When EasyJet first revealed services like the FLEXI fare and allocated seating, it's not changing their model to compete with legacy carriers.
If rolling out those services effected their low-cost model (eg. allocated seating slowed down turnaround times) they would simply not do it. It simply just gives them some extra added value.
EasyJet use this model the give them a cost advantage to then go in and penetrate the markets the legacies operate in (eg. BA at LGW, AF in CDG, KL in AMS) and gain market share through lower costs and lower fares. They don't need to operate connecting flights because as you say, they are able to do it with just P2P passengers and again operating connections would effect (negatively) their low-cost model.
Despite also what they say, they are not the best at opening up markets because as I say, they penetrate markets already well established. This reflects their claim that 75% of their new aircraft deliveries will be used on exiting routes and only 25% for new routes (it isn't made clear if they are exclusively "new" routes or just linking up more of the dots in their current network).
The real competition to EZY is as I say airlines like FR, W6 and DY as they are the ones who operate with similar business models to EZY in the sense that it's based on low costs, speed and efficiency.
FR competes with EZY but not just for passengers and market share, but also in the way that the business works and how it's structured, which is fundamental.
All I'm saying is I think EZY need to recognise that sooner rather than later. At the end of the day, you compete with who poses the most threat to you, and for EZY I don't believe that is the legacy carriers.