attaching a baby carrier / car seat to a vehicle seems easy, but a recent study showed that about half of US drivers had their seats installed incorrectly, and these are vehicles where the driver has unlimited time and resources to get it right.

I can't imagine that percentage goes up when strapped for time and under pressure during aircraft boarding.

https://www.nhtsa.gov/press-releases/national-car-seat-check...

My experience has been that as long as your car seat has the right certification they are allowed and the flight staff do check both that it has the certification sticker and that you've installed then correctly. The installation mode for planes is typically significantly simpler than in a car because it's just the belt pass through and seat angle. There's nowhere to attach a top tether.

You would be surprised.

Usually what I see happen is that people will wait until they are done checking seatbelts and then take them off.

> What parent in their right mind

As a parent, you would be extremely saddened to learn that many are not.