The lo co phenomenon is around a decade old. The IT market lasted around 25 years as a reasonably mass entity so it depends on where the market goes next. The IT industry grew because it was less highly regulated than scheduled services. Once scheduled services were deregulated, they expanded rapidly. Now people can, at least on short to medium haul, fly more or less where they want for a reasonable price so it's hard to see how you can improve on that. Long haul liberalisation is just a variation on a theme and will have little effect on the existing lo co industry. The future is probably lower capacity point to point (which is the market that Boeing is hanging its hat on). Unless of course there is a war, mass terrorism or the treehuggers get their way......
I've often wondered what would have happened if Donny International had been built before Jet2 came on the scene, or if Church Fenton had been developed instead of Finningley.