I have rigged all kinds of rubber contraptions to make them work better, I have made my own dynamos from old electric motors as a kid, and yet I have never in all those decades found a way to be sure they would work when I need them, never.

bikepackers aren't an homogeneous population. Some are more instagrammers than bikepackers and are using expensive bikes and equipment, others bikepack on a shoestring budget with stuff from the thrift stores and you could mistake them for homeless. And finally some are actually homeless. And you get any kind of budget and requirement/vanity level inbetween these 2 extremes.

This summer while I was cycling I came accross an ukranian guy who was bikepacking accross europe with an old mtb from the 90's, using an old kids trailer to carry his gear and water supply. He was stranded in a climb in the middle of nowhere with a broken wheel, 3 or 4 spokes had given up the ghost, and the tire was flat you could see the casing instead of the tread on both wheels. We could only communicate using google translate on my phone but he told me straight nomoney. His tent, which he had setup on the side of the road to have a bit of shade could have come from a dumpster judging by its state and discoloration, that tent was 20 to 30y old. Since my daughter has a folding bike with 20" wheels and I was 20 minutes from home I convinced him to give me his wheel, filled his empty water bottle with my own, gave him some snacks and went back home to check if spokes length matched any of my daughter's bike wheel and relaced quickly his wheel using 4 spokes from my daughter's. Then I climbed back that climb with the repaired wheel, 2 tires from my daughter's bike, a veggie sandwich and 4L of water (having myself a bike that is bikepack ready made it easier) so he could eat something and set off. He paid me with what he had available: a big hug and proposed to help me with my back (I understood he was some kind of chiropractor) which I declined.