I have literally never seen LLM writing that actually improved my life.

The model produces better work. Some of my peers believe that large language models produce strictly better writing than they could produce on their own. Anecdotally, this phenomenon seems more common among English-as-a-second-language speakers. I also see it a lot with first-time programmers, for whom programming is a set of mysterious incantations to be memorized and recited. I think this is also the cause of language model use in some forms of academic writing: it differs from the prior case with paper reviews in that, presumably, the authors believe that their paper matters, but don’t believe they can produce sufficient writing