I think the awakening is that Boston is still not a desirable place for NBA FA's. We all thought a chance to win a championship would be enough attract a good FA for less money. Well bottom line, it is not!!!
That's not true at all. If the Celtics had offered the same contract that the Hornets had, Posey would be wearing green next year. Corey Maggete also mentioned that he would possibly accept a MLE deal from the Celtics before getting offered $10 mil/yr. Eddie House, who got his ring, and has played in cities such as LA and Phoenix, decided to resign with the Celtics, even though he probably could've gotten more money and/or playing time elsewhere.
If anything, this past season totally disproved all the myths about players not wanting to play in Boston. Players essentially want 3 things: money, a chance to win and playing time. If the Celtics are able to offer that to a player, they'd gladly come. The problem right now is, with the team being over the salary cap, they can't compete with some teams in terms of money, so what they have to offer mostly is the chance to win. Some will take it. Some won't.
But the reason Boston wasn't getting anyone good before is because they really only had playing time as the only incentive. But if we're talking about good free agents, they'd get that pretty much anywhere, so Ainge never really had any leverage in the past.