That metaphor makes no sense at all. The commodity in question in that example would be "transportation" and the government can and should subsidize various forms of transportation for those with lower incomes. Nobody is proposing creating low income units that are incredibly high end in design and materials.

The government should definitely subsidize things like housing, transportation, and food. We're talking about creating low income luxury items. A house in Menlo Park is a luxury item, much like a Ferrari or Kobe beef.

A modest apartment is not a luxury item. It is a modest apartment in a place with expensive land values. Much like a packet of Oscar Mayer ham on dry white toast served at a five star restaurant is still a packet of Oscar Mayer ham on dry white toast.

The location in and of itself makes a house a luxury item. A cardboard box on a 20 square foot plot of land in SoMa is practically a luxury item.

But you can use the same roads as the Ferrari owners. Or should they have better roads than you?.