The NBA has been floating the idea of a midseason tournament (like European soccer) of some sort for a couple years now. If it works out that they are simply unable to hold a regular playoff, or an abbreviated version that at least comes close to maintaining the integrity of the usual playoffs, then maybe this would be a good time to try out one of their ideas for the midseason thing.
I wouldn't award the O'Brien trophy to the winner, it would be whatever other award they decide to do. It should also be noted in the record book that the winner is not the actual NBA champion. Unfortunately that will simply have to be left vacant. But it would at least give fans one last chance to see basketball before next season, and it would help a little towards making up all the lost revenues.
I could be wrong, but I thought, I read or heard somewhere that the NBA actually had something on the books that stated that if for any reason the NBA playoffs had to be canceled the owner of the best record at the time.
IMO, it would be a mistake to enact that. The people in Milwaukee may disagree though.