What is even more interesting is the behaviour of those who think a flight would be very risky but are happy to jump in a crowded van and go where thousands of people are congregating in close proximity.
There is much more science needed but given that many countries require temperature testing getting on and/or off and some do virus testing, you are already dealing with a likely lower probability of carriers on board, symptomatic or not. That and the fact that passengers are in a slower metabolic state, so less likely to be emitting viral particles by sweating, panting, etc. plus there are HEPA filters on modern aircraft that further reduce the level of pathogens in the air. That and mandatory mask use places a lot of barriers in the way of infection - these measures don’t eliminate risk but would appear to reduce it to a reasonable level compared with many other social situations.