While his comments may seem a bit extreme, they come in context of a recent New York City ban on large-size cups for soda pop. The role of government in these sorts of decisions is also a relevant issue at the federal level as conservative opposition to the Affordable Health Care Act has used the example of compulsory broccoli purchases as the logical outcome of the Supreme Court's recent ruling in favor of President Obama's signature legislative achievement.
Two things come forth from these discussions: an acknowledgement of truth and an acknowledgement of limits. Mayor Johnson puts it very well when he talks about the importance of cities having the feel of villages. While the city brings people close enough together to be advantageous on an economic level, human beings still have millions of years of evolving and adapting to the small-group setting of a hunter-gatherer tribe. While the endless opportunities of the city should, from an economic standpoint, give individuals the free reign to make choices that will make them happy, the similarities we share due to our human nature point towards cities needing be have certain characteristics. These could include cleanliness, easy transportation, and strong neighborhoods that allow for multiple interactions amongst people.
Nonetheless, the limitations of the government intervention model should be heeded. If we are to follow an account of human flourishing that derives partly from our evolutionary history, the modern nation-state does not fit well into that system. Aristotle's polis, or city-state, seems to be a much closer fit to what we are searching for. But this would suggest that a leader such as Johnson, who would be in favor of government "leadership" at the city level, may be more wary of it at the national level. This fits well with an American federal notion of democracy: at the local level, the people have more of an opportunity to use their government for good. As we abstract government to higher and higher levels, the ability of people to use their government becomes less and less possible. Thus, we should always keep in mind that government intervention has to be backed by a strong democracy in order to be effective.