Solarpunk

So for the cities and really rural areas I imagine it'd stay much the same. The cities and denser towns would probably still have humans walking a physical route through their neighborhoods, but between towns they'd hopefully transition from long haul trucks and airplanes to high speed trains. In places like rural Alaska and northern Canada, where post is currently delivered by fairly casual networks of pilots who just kick the thing out the door tied to a parachute, I imagine that's going to stay more or less the same too.

Everywhere else, where they're using jeeps and postal trucks for the last few miles from postoffice to house, a more solarpunk society would probably allocate electric or biodiesel vehicles to the job. I think a more solarpunk rural town might have denser communities and more conserved wild land, which might make some of their routes a little shorter (perhaps even short enough for train -> bicycle), but there are always going to be farmers, millers, sawyers, homesteaders, and other people who need/want to be out on their own, in addition to industries that are rural and transient enough not to justify establishing public transit, like lumber camps. For those places, small vehicles are going to remain practical. The postal service would hopefully still get close using trains etc, and perhaps the average driver might have a few options open so they can choose between say a truck and a motorcycle depending on the route and the load that day, but someone is going to have to drive it the rest of the way there.

I often look back at older ways of doing things, and I often find the more adhoc, human networks people relies on to be admirable. But in this case the postal service is something I hope would stay largely the same, as it does a great job despite a lot of polititians' attempts to break it, slashed budgets, and our society needing ever more rapid delivery. I hope something much like the USPS exists in a solarpunk future.