The reality is that the ship for that kind of privacy has shipped a long time ago. Like a hundred years ago. The reality is that the authorities know details about every single person that passes through an airport. You can’t get in or out without a passport/identification.
There is virtually no expectation to privacy at an airport. It’s a public place that is heavily monitored for good reason. And that fact isn’t hidden in the slightest. You are legally required to freely and honestly identify yourself to the authorities.
If this was at your local bus stop, then you’d have a point. But not at airports.
Also, the serious discussion about privacy should have started with the introduction of the smartphone. That’s when the conversation would have mattered and made a difference. But that ship has sailed.