Look, as a humble line pilot I am slightly out of my depth discussing flight planning policy. And so are you, may I politely add. I can only imagine that planning contingency upon contingency , because that's what a diversion is, a contingency, was not deemed necessary, maybe taking into consideration that you still have 30 minutes of fuel in your tanks after the diversion. I am not treating this subject lightly, I do understand your objections don't get me wrong. But I do think some people are very randomly cavalier with the amount of fuel they lift up.
Where do you draw the line? This is just the fuel we are discussing. Some would say that two engines are not enough...some would want four wings.