Due to the pandemic, global airline capacity fell by 58 percent last year compared with 2019, according to IATA. In the first week of this year, the number of scheduled flights worldwide was down 44 percent. Steep declines in airline capacity exacerbated an old industry problem: the inability of passengers to reach destinations aboard their originating airline’s aircraft. With demand at its lowest levels in decades, some industry watchers are looking for airlines to take a page out of the previous century . . .