It's always easy having the moral highground from he comfort of your home. Unless you have been in a life or death situation, you will never know how you will react no matter how much you would like to think you would do the 'right' thing. How do you even know you are in a life or death situation and not just well out your comfort zone? Our natural self defence mechanism are pretty good at tricking us into thinking we are beyone exhausted when we actually still have plenty of reserves left. If we find it hard to judge our own state, wouldn't it be quite arrogant to think you could judge someone elses condition, especially just based on stuff written in the news or social media?
Sure, the entire situaton could have been prevented had he been better prepared etc etc, but who here hasn't misjudged the conditions, their own fitness, knowledge gear etc?
I have done all the courses I could find, from navigation to winter mountaineering, climbing, scrambling, survival and so, plan my trips and gear with all sort of possible scenarios in mind and still I got myself into sitations occasionally that I probably shouldn't have been in... so why judge someone else? The guy will have to live with the knowlegde he let his dog die and it probably wasn't an easy choice so why give him more ****? What if he had young kids? Pretty stupid to risk the kids having to grow up withour a father figure over the life of a dog, no matter how much of a dog lover you are!
as for your questions:
1) of course I would never abandon my best friend, I would rather die alongside them (in theory, the reality would probably be quite the opposite but hopefully I will never find out)
2) I absolutely cannot stand dogs, so pretty unlikely I would ever need to think about that situation