I think SUL quickly got where it needed to be a few years ago, based on learnings from the mass of ultralight that was happening, and material advances that came with it. From here it will mostly be tweaks in performance.
Manufacturers, even cottage ones, will always be hesitant to offer truly SUL gear. SUL gear almost always relies on user skill, not just in operation, but in preventing it from being destroyed. In modern developed countries, consumer law is very heavily weighted to the customer. The burden is on the manufacturer to constantly make good of any damage to products they produce, even if they are used inappropriately. This is a big risk if you are trying to run a small business. Hence you see weight creep even in pioneering brands like GG and Zpacks.
In the last few years there have been some further good innovations for SUL.
Lightweight running vests and packs are starting to become more proliferous and much more comfortable. Prior SUL packs were basically just stuffsacks with what may as well have been string straps.
Inflatable insulating mats have taken big advances. The NeoAir (doesn’t work for me personally) is a huge advance, and Sea to Summit and others are producing similar matts at a comfort, warmth, weight level that was previously unheard of. Go back to 2006 and every SUL hiker used CC foam exclusively.
Cameras, in particular smartphones, have become far better. To get similar performance*Â in a digital camera in 2006 to what you get out of the camera of a mid range smartphone today, you had to carry at least a pound. To make SUL in 2006 with a camera was close to impossible in all but perfect conditions; SUL debates raged over whether one was allowed to include a camera or not!
Incremental performance improvements. In the SUL game, these all add up quickly. Even down quilts have advanced quite a bit… a cutting edge regular size 32F down quilt ran around 16oz in 2006. Same performance down quilt is now around 12oz. Thats a 25% weight saving!
Options. There are far more non MYOG options now for SUL. One can go spend $1000-$2000 online and be SUL almost instantly. You can much more easily be SUL now without having to run a poncho-tarp set up…in fact it seems like most SUL hikers now run seperate rain gear. This is a huge change.
I think things will continue to slowly evolve in the future with SUL. Advances in materials are still most definitely continuing, even in waterproof nylons. These all benefit SUL.
*Performance in a camera is pretty loose and dependent on a plethora of factors; specification, conditions, subject, skill, user preference… however in a nutshell, the ability of such a smartphone camera to enable the average hiker without a high amateur photography skill level to take good photos (on auto settings; in focus, exposed as per what they want in the situation…framing and artistic skill not withstanding)Â of the majority of their subjects, absolutely blows away the consumer digital camera market in 2006, especially anything approaching light enough to meet an SUL list.