There is too much political involvement needed to conduct a tournament and majority of the time these politicians cannot agree to a simple same logic and with all these constraints involved it is not an easy job for the ICC to determine the best possible solution until every board takes the responsibility on getting the permission from their respective government and then deciding on when the tournament can take place.
If the international travel resumes i do not think that we need a special permission form the government, i am not sure about the restrictions imposed in Australia and when they will be opening international flights and i do not think they will be closing everything down infinitely as it will have a huge impact on the economic structure and many companies will go bankrupt if they delay resuming business.
If there is a clarity when everything is set to resume then the ICC can resume with the tournament.