Bose and Sony have traded the noise cancelling crown back and forth for a decade, and both current flagships are excellent enough that either will satisfy most flyers and commuters. The differences are now in fit, sound tuning and small software touches rather than any dramatic gap in silence.
Bose tends to win on physical comfort for longer sessions and on cancelling very low, steady rumble such as jet engine drone. Sony tends to win on sound customisation, multipoint reliability and battery life on paper. Neither is a bad choice; the decision comes down to your head shape and whether you tinker with EQ.
Below is what actually separates them, a side-by-side comparison, and honest answers to the questions people ask before choosing a side.