There is endless fun to be had imagining what the world will look like when this ghastly crisis is over.
Will the age of cinema and movie-going be over? Will office workers ever see the office again? Will we fear the touch of strangers?
In the aviation industry it really matters. No other industry has been closed down so completely. What do the world's top industry experts think?
When will it take off again?
"We are in this mess for five to seven years," is the bleak assessment of Volodymyr Bilotkach of the Singapore Institute of Technology and author of The Economics of Airlines.
He reckoned that passenger numbers globally could return to pre-COVID-19 levels the year after next but "normality" would take longer.
"Even if we get a vaccine - even if there is lasting immunity," he told this newspaper, "for some time, we will still have to live with the health and safety measures which have been introduced during the pandemic."
In Hong Kong Airport, for example, they introduced temperature testing of passengers after the SARS outbreak in 2003. It never went away.
Similarly, Dr Bilotkach thinks measures like deep-cleaning aircraft and a lack of in-flight food may become long-lasting.
So might anxiety.
What about airports?
Dr Bilotkach thinks smaller international airports such as Canberra are better placed to bounce back than the monster airports which churn through batches of 800 passengers emerging from the double-decker Airbus A380s.
He thinks the future belongs to smaller, single-aisle aircraft flying longer distances. Their range now extends from Australia right up into Asia.
Is he a lone voice of doom?
He is not.
"We are going into a new dynamic which we don't understand," Hugh Ritchie, chief executive of Aviation Analysts International, said.
He thinks biological security will be as important as anti-terrorism security became after 9/11.
And you can't just get into a plane, turn it on and fly off.
I think Australia needs to grow some balls.- Hugh Ritchie
Many of the world's passenger aircraft are now in deserts, including in central Australia. They will need to be brought back up to technical standards. Pilots will need to be retrained.
Mr Ritchie agrees with Dr Bilotkach that fear of crowds will change the balance towards smaller airports.
Singapore Airport manages 72 million passengers a year, with a population in the city-state of four million.
Smaller airports, in contrast, can deal with fewer people and link with each other.
He thinks that mid-sized planes such as Boeing's Dreamliner were the way forward for international flights.
Their rise in the market meant airports like Launceston in Tasmania and Canberra were well placed for the new era. "These airports are manageable," he said.
"In Sydney everybody pushes through. Canberra can manage the people," he said. "Regional airports are fine. Canberra is fine."
"If I was going to invest in airports in Australia, I would invest in regional ones."
Where do governments fit in?
They don't is the angry view of a lot of people in the industry.
Mr Ritchie's company advises airlines all over the world, particularly in the Middle East.
He is normally based in the Indonesian capital, Jakarta, but finds himself trapped in Sydney. There are, no doubt, worse places to be trapped except his wife is at home in Indonesia.
He thinks the Australian government has been far too ready to close borders - and so close an industry.
"We have ramped up the fear factor too far. People are so scared of catching this thing that they don't want to go outside."
"I think Australia needs to grow some balls," he said.
The dismay at governments is shared by the International Air Transport Association, which represents 290 of the world's airlines.
Its director general, Alexandre de Juniac, said that 90 per cent of international flying had stopped.
"What is killing aviation is the fact that governments are not managing the risks of opening borders. Instead, they are keeping global mobility effectively in lockdown," he said.
Where does it leave airlines?
Often with a begging bowl.
In the United States, The New York Times reported: "The Trump administration has reached an agreement in principle with major airlines over the terms of a $25 billion bailout to prop up an industry hobbled by the coronavirus pandemic."
The federal government's Australian Airline Financial Relief Package amounts to $285 million.
In Europe, some bigger airlines and profitable low-cost ones have said they don't need state aid and have lobbied against it for their weaker rivals.
But national governments have propped up some smaller airlines like the Swedish, Serbian and Belgian flag carriers.
Is a shake-out on the way?
If this thing goes on, there's no doubt airlines will fall.
Qantas is probably too big and too important to Australia's image for the government to allow it to crash but Virgin Australia is already in trouble.
Smaller, local airlines are looking on with interest.
Pelican already flies from northern New South Wales to Canberra.
Regional Express Airlines (Rex) has a network of small destinations from the Northern Peninsula Airport in Bamaga down to Burnie in Tasmania and out far west to Monkey Mia in Western Australia.
Maybe they're the future - but there'll be turbulence on the way.