"The 3 common issues used to be solved by a manual with an FAQ page, or just you know, actually intuitive and usable software and hardware."
Having led customer support, this grossly misunderstands how people interact. People don't read. It's as simple as that. You can write something as clear as day in a FAQ, and they don't want to put in the effort. ~50% of the inbounds I receive are fully written out in plain language in an FAQ.
LLMs are perfect for this scenario. It puts the answer in clear english and will endlessly re-word the answer when clients followup.