Another factor not addressed here is to get one's wheels checked by a skilled wheel person every so often.
I pretty much did this before any loaded trip, so by having spokes at the proper tension helps keep a wheel true, so less unequal tensioning that happens to counter an out of true wheel, which leads to a harder life on spokes and rims in general.

but yes, a properly tough wheel/rim and spoke type/count help a lot to a wheelset holding up well over time for a given rider and load weight, no way around that.