Highway 401 in Ontario is the largest highway in North America, up to 18 lanes wide. It moves 500,000 cars per day; fewer than a single subway line.
The incredible cost of building and maintaining it, the cost of 500,000 cars and fuelling them, the enormous land use, the environmental cost of the concrete, the idea that you could have a pleasant place to live or work near it... but we can't have trains which move more people, less pollutingly, less dangerously, in less space, are nicer to be around, and overall costs less, because it isn't profitable? As if Highway 401 is profitable?