Firstly thank you for such a thoughtful and long reply. You are right about LLMs reducing cognitive overload and helping you concentrate on the core problem. I avoid them for environmental reasons too.
I too am not a fan of boilerplate and tedious languages like latex.
My approach for dealing with it is using better abstractions like typst. When I was seriously writing LateX years ago I had emacs macros and shortcuts to power through the tedious parts.
I also choose modern programming languages like gleam instead of java or js. They are easier to reason about and write fast manually. IME you can overtake the productivity gains that LLMs offer after 3-6 of working on a project.
Fun fact: large energy expenditure even from renewables is subject to the 2nd law of thermodynamics. It heats up the planet.
So I prefer to do everything the old fashion way with principles of frugal computing, offline docs, local editing, and try to keep as much in my brain as possible.
I don't expect others to do the same. It's about how much convenience you want to sacrifice to live a wholesome life.
edit: It makes sense from the perspective of keeping your brain young too. The more you use it even for "tedious" tasks like navigating instead of relying on gps, learning languages, doing mental arithmetic instead of using a calculator, memorizing phone numbers, and writing manually etc, the better it'll function especially after middle age.