Some quick thoughts.
The speculation on the cause of this is pointless unless you have very specific knowledge of
handling the big jets, and this specific flight. Uninformed speculation is boring. Grounding all 777s? Come on...
I'm really impressed, from a distance at least, at how Emirates has handled this - their media plan worked, the website has gone monochrome for a while and there seems to be no ongoing calamity with flight delays and cancellations.
I'm also impressed at how the Emirates board has reacted. If this was certain other forums (ahem, BA), there'd be uproar.
None of us have any idea of how we'd react in this situation, stopping to get luggage is dumb but oddly understandable. I'm a pilot (of little planes) and have practiced emergencies hundreds of times, and therefore I'm the kind of person who actually thinks what they'd do sitting on the exit row, but I can't predict what would happen if I was in a crash as a passenger. Darn sure I'd look out the window to check for fire though, and make sure I'm sitting near an exit.
I've learned from FT to have my passport, phone and a couple of credit cards in my pocket when taking off and landing. The experience of passengers on the BA flight that crashed at Heathrow a few years ago was that, without a passport, they were stuck in the lounge for a very long time. With a passport, they could have gone home.