There is a relevant section in the book “QF32” by Richard de Crespigny in which he gave his account as the Pilot in Charge of the Qantas 380 which suffered catastrophic engine failure after leaving Singapore.
After the plane had successfully landed again at Singapore they began the evacuation using the escape slides and the passengers were told to leave all their luggage and bags on the plane. One passenger turned up at the door with his rollalong bag where he was stopped by the CSD. The passenger’s attitude was “Well I’m here now, what are you going to do about it”. The CSD took the bag and threw to the other side of the cabin and then ordered the passenger down the slide.
They had a little more time for the evacuation than the BA plane in Las Vegas, but not a lot more. I firmly believe that passengers need to be told on the Airline’s website, in the inflight magazine, in the safety briefing, and in the safety card in no uncertain terms that they can’t take their belongings with them during an emergency evacuation. I agree that they should make an example of the relevant passengers on that BA flight.