I don't think so. Looking at S10 Jet2 appear to have cut frequencies on a number of routes outside of the school holidays. It looks like they have tried to maximise yields and have possibly come unstuck.
If fares are too high, people go to other airports and LBIA will be keen to prevent that (as would any airport!)
I don't think J2 will suffer overly - 14 destinations on 2 aircraft means frequencies will be relatively low, but it might keep them honest. The public should win - better fares and more services. The Leeds catchment area can stand the extra services so in my opinion everyone can win.