I honestly can’t understand why it’s not more widely adopted
Because it’s an expensive, messy, faffy method that will clog your mech pulley wheels and clog your cassette (unless you spend more time wiping the excess off) and permanently stain any fabric in comes into contact with, that probably gives marginal improvement over normal lubes at best, and in extremis is really no better than most off the shelf dropper lubes. For me at least, having tried many, I’ve found one that is the opposite of all of those. I may have to apply a bit more, but as it’s part of my cleaning routine, I don’t notice, and my chain and cassette last well enough.
Give it a go by all means, and if it works for you, hoorah! but it’s not the ideal solution for everyone, despite it’s users often evangelical proclamations of it’s magical properties. 😉