If they just operate 2 or 4 times a week often with poor times, on routes where Jet2/Ryanair already fly more in a day than they did in a week, and you don't bother advertising the fact, it isn't really surprising that flights weren't as well booked as they would like, but, it has always been the case that airlines expect new routes to take a year or two to become profitable. Easyjet haven't given them that long. They have even axed Belfast that does have good loads and Paris too, abd Barcelona that was doing ok.
Something has clearly changed at Easyjet with a plan to gradually increase their presence towards a base, suddenly shelved, amid a statement which makes clear they don't have the aircraft to open another base before 2030. If they are short of aircraft in the next few years, it is inevitable that non based flying will be first up for the axe. Their exposure to high fuel prices as well has probably turned their LBA operation from marginal (as expected) to loss maker, and a reported 70% drop in profits has probably forced them to
They are still new routes. You can't claim we haven't had any new routes in years, because clearly, we have. What we need though are new routes that are not necessarily bucket and spade routes, which would be operated by other carriers. The likes of Istanbul, Athens, Berlin, Lisbon, Madrid, Valencia, Munich, Frankfurt, Milan, Cork etc. These 'other carriers' are precisely those who won't entertain LBA until terminal regen is finished.