There are no easy solutions-- a multitude of factors have worked together to create this situation.
Neighborhood Character Might Not Be What We Think
Point-Counterpoint on Sidewalk Funding
Point and counterpoint from City Lab and the Urbanophile talk about the pros and cons of having the governments directly maintain sidewalks.
More on two way streets
Strong Towns provides some case-studies as to how two-way streets can create a vast improvement.
The Price of Walkability
demand for walkability increases costs for housing in walkable neighborhoods.
Letting the Tenants Save the Building
The truth about displacement
Not fixing housing in CA
Parking or Affordability?
Parking is one of those costs, and requirements to build parking increases the costs of homes.