One problem with rebuilding a technological civilization is that it's built on the availability of energy resources. You start with wood then coal, oil, gas, then nuclear for example. They tend to build on each other and each one requires the energy production of the one before. If you need to rebuild from scratch you may have already used up the easily available resources from before.
No. May be some resources are depleted, but look at the earth today. Let's say nuclear war happened and we have 2-3 millions scattered around the globe. Do they really need to burn as much coal as our ancestors did to obtain steel? No, they will scavenge existing resources. Plenty of steel. One single steel bridge is going to be The Source of good steel for everyone to maintain XIX AD level of technology. No need to smelt iron at all. Think about all railroads and other steel structures that will last for many, many centuries. Think about car engines of aluminum, ready to be melted with little amount of charcoal. Think about all the glass around. Think about all asphalt roads, you can turn them into the fuel in primitive furnace. Etc, etc. Advancing into XX century is hard, yes. But not impossible with solar wind power, especially if basic scientific knowledge is preserved.