It's not just a matter of including everyone in the discussions. The difficulty is that the planners begin with a superior, elitist attitude and a way of thinking and a plan that are, for them, foregone conclusions. Just "listening" to the ignorant and prejudiced masses have their say and express their objections won't be enough. 

People's neighborhoods are not just an externality for them. They cannot see them essentially changed and then simply "adapt" and "get used to" the changes once they see the superior wisdom of the planners. The neighborhoods are their lives. Their emotions and stories and memories and their hopes and their days are lived out and have meaning in their neighborhoods. Many hope to retire and then age and die in their homes, in their neighborhoods. They know things will change. That is acceptable. What is not acceptable is to say that their lives are grounded in ignorance or prejudice, that the planners know better about what a good neighborhood is than they do.