Urgent? Absolutely not, if the tech is there for me to call, I'm going to call.

I agree that a planeload of screaming passengers is not ideal, but the fact is many modes of long haul transportation like Megabus and Amtrak do not prohibit calls. People do call, and people get along just fine. I even sat on a 5 hour Megabus next to a woman who was apparently breaking up with her boyfriend and spent the entire trip time on her phone. Nobody complained and it was not a nuisance (trust me as I was the nearest passenger).