Load factors are not a guage on profitability, yeild is! You can fill an 800 with 1p fares or half fill with £9.99, guess which route would be chopped?
Klagenfurt will feature from Luton as the yields against the hike from introductory airport prices, means that Ryanair cannot make enough money from the route.
If you do a search on this site under Carinthian Spirit, I was well ahead of the game!