And I disagree with you on this point Chad. I think that there is a great deal of trickling down of ideas between genres of backpacking.
I think lw backpacking has had an impact on traditional backpacking and mountaineering as seen in trends toward lighter weights and fabrics.
I also think that alpine-style mountaineering has had a big impact on ultralight and SUL backpacking (poles, bivies, etc.)
And I think also that SUL/XUL backpacking is having an impact on UL backpacking too. If you look at cuben and spin fabrics used in full-bug shelters or trimmed frameless packs, tarp/bivy combos, or any radical trimming of weight, you'll start to see the influences. It's the guys pushing the limits that first bring these items into the field.
That said, the influences are not for all. There are a lot of folks that lighten up to a certain point and call it good. For them, SUL may be entertainment, or possibly idiocy. But for many others, I would suspect that learning about these lists and techniques has had some influence…at least in seeing what's possible.
That's why I have enjoyed my SUL sub-4 base weight trips- they've opened my eyes to what's possible and have built my backcountry skills. And they've also made me really appreciate the other items that make their way into my pack for most trips. And at the end of the day I get to choose my style- and that's good for me.
To each his own. And influences are choices that we make as well, along with our criticisms. Black Sabbath had fans and critics, as will XUL and just about anything that pushes a limit.
Best, Doug