You're likely much more effective giving up your car than giving up flights.
https://ourworldindata.org/co2-emissions-from-aviation
https://www.epa.gov/ghgemissions/sources-greenhouse-gas-emis...
That's because most people in the world don't fly. If you're flying coast to coast and back once (approx 1t CO2eq), that's already a significant percentage of a typical car's yearly emissions, like 20%. Add an international flight and you're getting close to an even split.
> You're likely much more effective giving up your car than giving up flights.
I mean, obviously ideally you'd do both. Probably easier to significantly curtail both instead of giving it up entirely. But telling most people to give up their car is like telling them to give up a kidney or both.
Many of the people I know who work remotely live in areas where they are highly dependent on personal vehicles. Some of them moved to more remote areas where they could get bigger houses which require more heating and cooling. Given a person who lives in a smaller, well-insulated apartment in the city and has a short commute by public transit, bike or on foot, vs a person in a 2000 sqft mcmansion in the exurbs who works in their home but needs the car to go to the supermarket, who has the smaller footprint?