I agree there isn't a credible source behind this, but the NHL shutdown is enough precedent to conclude that this might be a possibility, moreso when Bob Batterman is on the NFL lawyers team. Rumbling or not, I see the owners taking this route if the terms of a new CBA are forced to them.
I didn't invent the "nuclear option" term. It was first used by the media to describe the antitrust lawsuits the players were going to fill after a possible decertification.
I know shutting down a league is not simple nor cheap but I see the owners saying this is enough, the business it's at an all time high but it's probably very close to it's peak of growth. If that is the case, when is enough for the players to get more? it's evident the owners (who know a thing or two about economics) are not happy with the last business model and see no more venues to squeeze a potential large revenue to share with the players.
If I were an owner and my accountant is telling me that certain business model is unsustainable, not for the now but for an eventual future, you better believe that I'm listening (no matter how good the business is) If I have to lose now to earn more in the future, I buckle up and take care of my business before it's too late.