I assumed fast walking to be 5 km/h and you said 2 hours.
I’m totally with you, but the US mobility problem is fucked since the 1950s and now there’s no easy solution. The bigger picture is that every investment into car-only infrastructure will hurt the working poor and precariat.
A short-term solution could be raising fossil fuel taxes and subsidising people who cannot afford any other mode of transportation with a part of that money.
The mileage of 6 miles (10km) isn’t going kill you, I’m talking about the bigger picture of cheap cars fueling urban sprawl with little spatial income density and we haven’t talked about subsidy inequality yet.