Guilt-Free Flying?

There's been a great fanfare for Virgin Atlantic's flight VS100. This flight was partly funded by the UK government. Its being hailed as the first transatlantic flight using '100% sustainable jet fuel' and a means of producing 'guilt-free flying' (https://www.theguardian.com/business/2023/nov/28/transatlantic-flight-sustainable-jet-fuel-virgin-atlantic-saf). Flight VS100 used cooking oil as fuel, rather than kerosene, cutting down on fossil fuels. So-called 'Sustainable Aviation Fuel' (SAF) is attractive to airlines as it requires minimal modification of existing aircraft. It has, however, some problems. Firstly, SAF's current availability is less than 0.1% that of kerosene. Secondly, its production competes with that of agricultural food production. Agricultural land is declining, as the world human population increases and climate change exerts its pressures. Thirdly, SAF is still carbon dioxide in: carbon dioxide out. Fourthly its use still generates contrails high in the atmosphere thatincrease global heating. Finally, using SAF reduces incentives to radically change flight technologies. We are a long way from 'guilt-free flying'!