Surely of the things that need to reduce their use of fossil fuels air travel is the lowest priority. From memory its less than 10% global CO2 emissions but provides a near irreplaceable utility. Covid hysteria has already caused a long term ramp up in costs and removal of this utility from millions of people's affordability - which in a very global world is a huge step backwards.
Not to mention the reconfiguration of the entire industry prompts questions about safety - how feasible is it to replicate 60 years of conservative engineering changes to current commercial airplane designs? In principle they can design to modern regulated standards, but the reality is those standards are based off millions of hours of flying time per manufacturer/design/model as evidence for effectiveness followed by iterations on those already proven designs.
Not to mention the reconfiguration of the entire industry prompts questions about safety - how feasible is it to replicate 60 years of conservative engineering changes to current commercial airplane designs? In principle they can design to modern regulated standards, but the reality is those standards are based off millions of hours of flying time per manufacturer/design/model as evidence for effectiveness followed by iterations on those already proven designs.