For what it's worth, in the same situation, I would have an a very good idea that there was something amiss and because I know that it's a very busy time for all the crew, I wouldn't be too concerned, I would accept that they are people who can resolve the problem and would sit back and let them get on with it.
However, the vast majority of passengers are not aviation professionals, they don't know what goes on when something unusual happens and they are entitled to be told something, even if it is a firm announcement from the cabin services director that they are to remain in their seats, a minor technicality is being dealt with and further information will follow.
As a long standing aviation professional and a very regular traveller, it strikes me that the airline operators (NOT the crew) are too reliant on pre recorded safety briefings and there is very little inter personal contact with the SLF.
I know that todays market is all about rush rush rush, make a profit and bugger what the customer thinks, but a little more inter personal contact with the people who provide the custom to airlines would make a big difference in the thinking of passengers perceptions and opinions.