I think one of the impediments to adopting UL concepts is that many different types of activities are all lumped into one category called backpacking. There are at least three quite different activities (and likely many more) that are all called backpacking. The one that benefits most from UL concepts is hiking. When the activity is the hike itself. UL concepts are a large benefit here. Another activity is camping. This is where the hike is only a means to get to the destination. The shorter and easier the hike the less benefit (and the larger the sacrifice) UL is. The more time you spend in camp the more “luxuries” you want. The last one I don’t have a label for, but is where some other activity (fishing, hunting, photography, etc.) is the reason for carrying the pack. UL concepts may be a huge benefit here, or may not; it just all depends on the equipment desired for the activity, the difficulty of the hike and probably the amount of time spent “in camp”.
UL concepts are a benefit while hiking. If that is already easy enough the concept of making it easier while doing without something is a harder sell.
BTW, I go camping every year with a backpack. I carry a base weight of 38 lbs. I UPPED it this year to provide more comfort while in camp. The consumables were significantly MORE than 38 lbs (its downhill all the way into camp).
This year I went hiking in Yosemite. While I left out many of the luxuries from the camping trips I still ended up taking things I could have easily done without. I quickly learned that the less time spent in camp the less you use. ;^)
The gear needs to fit the activity.