There are cheap high-density areas and expensive low-density areas. According to your and that blogpost's logic, Silicon Valley's high housing prices in single-family neighborhoods and the fact that people want to move there are proof that people ACTUALLY want a suburban lifestyle, not an urban one.
Looking at where people live and where they want to live is a better source of their actual preferences than looking at housing prices in a handful of expensive neighborhoods and guessing what the average person wants.
Sure, as long as we also get rid of all urban growth boundaries. Be careful what you wish for, a free market city won't look like what you think it will.
They already do in many places. Toll roads exist, and the gas tax pays for almost all of the highways anyways. Transit is subsidized an order of magnitude more. A world with no subsidies looks more like suburban sprawl than a dense transit focused city.
Looking at where people live and where they want to live is a better source of their actual preferences than looking at housing prices in a handful of expensive neighborhoods and guessing what the average person wants.