Just to add a brief indication of agreement with PilotLZ . . . as recently as the autumn of 2019 one could pick up any of perhaps dozens of officially published ICAO reports and documents, all of which would breezily look ahead to a "doubling of traffic" within some nominally short span of years. It was as if Rosy Scenario, the mocking name given to projections and forecasts issued by economists, had taken up residence for good in the world HQ edifice in Montreal. (IATA too, though somewhat less emphatically, IIRC.)
But cheap shots at ICAO sunny optimism isn't the point this SLF/attorney (with an increasing emphasis on public and private international air law) wants to add here (or before heading over to Jet Blast). Instead ICAO was heavily invested organizationally, it seemed, in CAPSCA, a group of various international and/or professional bodies focused on how international civil aviation could prevent future public health events from becoming epidemics, let alone pandemics, let alone the crippling, eviscerating crisis that has befallen the airline sector worldwide.
This SLF poster has not drilled into what CAPSCA's work program might have put onto websites prior to the COVID pandemic, looking for its own Rosy Scenario in order to take more cheap shots -- at its studied and, evidently, undeniable ineffectiveness writ large. Still, it does seem relevant to ask where CAPSCA so badly missed the salient points in its work until the pandemic struck; perhaps highly relevant to ask. I recall a date when the novel Covid-19 coronavirus was just entering the news, and a public health persona (somewhere between luminary and huckster) posted on social media that the WHO had declared a PHEIC. We all knew what that meant, right? (.......Public Health Emergency of International Concern, a level or two short of....you get the point).
There's a great old Party Joke about Rosy, but like I said, before heading over to Jet Blast where all SLF/attys should go sooner or later.