Planners and many others like urban "density". The 1974 Costs of Sprawl report and hundreds of sympathetic tomes (look at the Sierra Club's "Ten Reasons Why Sprawl is Hazardous to Your Health") provided a focus for various antipathies, particularly those focused on auto travel and personal mobility (and choice). This is an old story. People keep making choices their betters disapprove of.
But the plot thickens. Most urban and regional plans are full of policies to reverse "sprawl" and promote densification. More public transit ("light" rail is the current favorite), more transit-oriented development. More investments in old downtowns, etc. A 2006 Brookings Institution study sought to classify and categorize all of the planning approaches.
Have they worked? Look at U.S. urbanized area density trends. They do not line up with the policies. The Brookings study itemized the many types of measures that planners throughout the U.S. have adopted. The last column of Table 3 of the urbanized area data link indicates thirteen urbanized areas which experienced increased population densities in the most recent decade, the period during which the policies studied should have had an effect. There is not observable connection between increased population densities and regulatory approaches as identified by the Brookings study (Table 3 of their study and their Appendix).
Th researchers surveyed 1,800 jurisdictions which reported planning efforts in six broad areas of land use regulation (zoning, comprehensive planning, containment, infrastructure regulation, growth control, affordable housing). These were represented by twelve policy measures. Factor analysis was applied to classify the metropolitan areas in terms of their dominant regulatory approach, e.g., twelve "clusters" of policies. The study authors then arrayed the clusters into four "typologies of land use regulations" ("Traditional," "Exclusion," "Wild West Texas," "Reform"). But the Demographia density report (Table 3) shows that very few urbanized areas experienced increased average densities. The few that did were scattered across the four typologies. Houston, (as in no traditional zoning and as in "Wild West Texas") was one of the few. Houston, do we have a problem?