I believe that was shortly after the war, when the family only had realistically about 20 active members supporting the leadership. Remember, Orena's faction was numbered at 75 men whereas Carmine's supporters were numbered at only 25. After the war, the near entirety of the leadership and capos from both sides were locked up, a huge portion of the family's soldiers, and a number of prominent associates. Informants were lining up from every angle. Orena members often feared repercussions from Persico's side, or they were unwilling to accept defeat, or they were simply unwilling to shake hands with people that were just trying to murder them.
In terms of recovery, the Colombos came back from the brink. There's no doubt about that. They're still the weakest of the five families, but they have 76 members (at my last count, excluding recent deaths) and we know they are actively recruiting new members and conducting new making ceremonies (a confirmed ceremony in 2014, and a reported ceremony last year). Even putting them at a conservative, say, 50 active members, they are still in far better shape - both in terms of numbers and organization - than they were when the discussions about dismantling it were held.