The speculative comment lays out a scenario under which Brexit might be averted. A redux of the argument goes like this:
British Prime Minster David Cameron had said that he would invoke Article 50 — which establishes a timetable for formally breaking up with the E.U. — if his country voted to leave the E.U. In fact, he'd said he would do it the morning after. Instead, in announcing his impending resignation, he may be trying to shield his legacy by passing the responsibility of triggering a potentially catastrophic Brexit to his successor.
Given that Cameron's likely successors are Brexit supporters from within his party, one might think that they would simply go ahead and invoke Article 50, setting the E.U. pullout process in motion. But, as Teebs notes, these likely successors have been quite subdued in their remarks since the referendum — and some are nowhere to be found.
Boris Johnson, London's former mayor and a favorite to succeed Cameron, has said that there is no need to trigger Article 50 right away. Other "Brexiteers" from within Cameron's Conservative Party have simply avoided the question.
In other words, the consequences of Brexit are so stark and may hold such disastrous implications that Cameron's successor might hold off on invoking Article 50. As Teebs puts it, "The enormity of that step started to sink in: the markets, Sterling, Scotland, the Irish border, the Gibraltar border, the frontier at Calais, the need to continue compliance with all EU regulations for a free market, re-issuing passports, Brits abroad, EU citizens in Britain, the mountain of legistlation to be torn up and rewritten ... the list grew and grew."
It doesn't seem as if anyone is stepping up to that task yet.