It's affordable, financially, for a vast swathe of the population to fly (with Ryanair or other budget airlines at lewsy) abroad and every year millions of people do so. It wasn't normal until perhaps the 1980s, but how many people do you know who haven't flown abroad for pleasure at least once in the last 3 years?
I can't find the pdf of the full article rn but this article in nature :
Shift the focus from the super-poor to the super-rich
Makes the case that the super rich (the richest 47 million people on the planet I believe) emit as much as the poorest 3.5 billion.
Admittedly those 3.5 billion probably don't do much flying.
But my point is : while massively increasing the cost of air travel would dissuade people from flying so much, it would punish the poorest fliers.
Is that the right way to convince people to change their holiday plans? It won't make much difference to the rich. Or those with private jets.
I havent seen any models, I don't know if any exist, but imagine the cost of all flights doubled overnight. Would the number of flights halve? I doubt it somehow. I'm not sure how effective a measure it would be on its own.
On the other hand I would be in favor of:
Government bans on farms which host more than 100 animals
Buy back and replace subsidy schemes to take diesel and petrol cars off the road
Nationalized electric cars
Wind, tidal and other renewable energy expansion
Nationalized power rapidly converted to renewable
And so on
But unless it's global again, the UK alone wouldn't make much difference. China, Saudi, Russia and the US: without them fully engaged in the same activities its all a bit pointless denying yourself a Ryanair flight out of climate guilt