I’m betting we will never find out. The number of people who have been driven out of air travel because of today’s draconian restrictions is basically zero. People are conditioned to comply with any request in order to board an airplane.

EDIT: you edited your post after I posted. As long as you don’t make people uncomfortable on the plane, that is. Don’t take away their phones, laptops or headphones, and you can grab as many images as you want of their irises, retinas and fingerprints.