A woman was performing her job and a guy humiliated her in front of an airplane full of strange people. It's not simply the "cat call" persay but think of how humiliating that is. The 'guy' (not to be confused with Man) sexualized her in front of people that she is suppose to be responsible for. There is nothing ok about it! 
Men are suppose to protect women not subject them to humiliation and abuse. Guys that do are cowards and have serious self esteem problems, that is an established fact. What's missing in this society is another male passenger can't punch him in his mouth because in a not to distant past that's exactly what would have happened.