SwissRef,
As a captain, one of the first questions that I ask a dispatcher is "what have the passengers been told"? The vast majority of the time they will have purely passed on third-hand information.
If there is any kind of lengthy delay that does not allow me to board passengers I will do my best to go up to the gate and inform the passengers myself. I prefer the proactive approach because it avoids any misinformation and also ensures that passengers arrive at the aircraft in a better frame of mind - certainly less grumpy!!!
Cold weather operations can often throw 'curved balls' at you, and I am certain that my colleagues did not just ignore their passengers or knowingly allow you to be given duff gen.
Please remember that the prime role of the aircraft captain is to get you to your destination safely and securely. If additional de-icing is required I am sure that he was spending the vast majority of his capacity thinking about your safety. It sounds like there was not enough time, spare capacity or whatever to also be proactive.