Strange! I would quite specifically highlight “having to do the reader’s thinking for them”, as well as more generally developing the skill to “communicate non-interactively with an unknown audience”, as extremely valuable upgrades to my thinking.
Most valuable thinking is done at the margins, where you don’t have much capacity to emphasize with a diverse and unknown audience.
That said, abdicating to an LLM is the worst of all worlds - you’re not thinking and the product is not tailored.
The solution is obvious - write as much detail as you need and allow readers to interrogate the virtual you with an LLM, maybe not even reading what you write.
It's a kind of shared fiction of an imaginary person's thinking, really. The author writes "now, I know what you must be thinking", and hopes the reader will agree "OK, close enough".