It's not industry wide. Ryanair at STN seem to be very stable and reliable.
I could understand that over half term with large crowds, Easyjet was having to deal with a short term surge, and operational reliability would suffer. However post surge, they still seem to be chaotic. Easyjet know the numbers of crew and aircraft available... I don't see why somebody senior at HQ cannot decide *in advance* what is operationally achievable and what is not, and communicate this publicly. Tell people in advance, and they can work around it (and Easyjet can avoid EU261 claims) - getting an email while in the car to the airport to say the beach is cancelled is far too late.
Running an airline with a large leisure focus is about taking money now in return for delivering a service in a month or more. Without consumer confidence that the service will be delivered... the consumer will purchase from another airline, including those high-fare (and profitable) late notice bookings