Bargaining allows escape that prisoner's dilemma doesn't

Taking a meta step to escape an inequitable equilibrium is more plausible in bargaining than in the prisoner's dilemma: in the prisoner's dilemma even allowing communication does not guarantee cooperation (the only equilibrium is bad), whereas the bargaining game has a fair equilibrium available—but conversation alone may still fail because those getting more benefit from getting more and often engage in special reasoning to justify the status quo that benefits them.