jackk> surely do not take their advice.
I think the issue is more that they are interested parties. As R Meir Twersky wrote – we value human life more than others, as their cheshbon is more of money v. health. And also airlines have bad record of providing safe air. They were never bothered by people getting sick on the plane.
And they chose their words carefully: it is safer than other indoor environments (they did not specify which one). So, those who are used to sit for hours with tens of other people in a room with bad ventilation and closed windows, will be safer in the air. I think research supports that. Not sure what is wrong with the mask though as it sure protects you from your neighbor’s sneezing.