It’s a change in mindset that’s needed - the cost of flights doesn’t represent the actual environmental cost, and for people of a certain age, they came from not being able to afford to fly in the 60s/70s, through to the 90s when the cost of flights came down and companies like Easyjet sprung up where it was cheaper to fly to Spain than it was to drive to Devon for example.
Part of me is with you that people shouldn’t fly, but there’s another selfish part of me, which I’m not proud of, which thinks about what the situation might be like in even five years time when attitudes (and cost) will be more in line with the impact flights have, and that if you’ve got the opportunity now to take it before it goes away. (Although for a lot of people they might be completely oblivious to this situation and are just flying place because they can)