The issue is, broadly speaking, that holidays are supposed to be fun and relaxing. This is not fun and relaxing:
1. Masks from moment you enter your departure airport to moment you leave the terminal at your destination. Even for a short-haul flight this could be 5 or 6 hours.
2. 'Traffic light' style 'on / off' lockdowns at destination venues - do you really want to be stuck in a hotel room for 2 weeks?
3. 'Traffic light' style 'on / off' requirements to quarantine when you return to the UK - you could go when everything is ok but come back to find you are stuck at home for 2 weeks.
4. Minimal 'service' at hospitality venues when you get to your destination. Plus requirements to socially distance and wear masks everywhere. In 30 degree heat!?!
Testing at airports will not be the silver bullet - the tests are producing a lot of false positives and there are major questions about how much Covid has to be in someone's system before the are declared to have it. As for thermal imaging - who wants to book a family holiday then be refused permission to fly because someone's temperature is slightly off on the day. 'Covid refund guarantees' seem to mean nothing - airlines are being really tardy about refunding money.
Public confidence is shot. People are not going to fork out thousands of pounds to go on an 'enjoyable holiday' until a reasonable solution is found to all of the above.
Very deep concerns about the future of the industry which, of course, does not just involve pilots and cabin crew.