I can relate to the inclination, but so many new insights and moments of inspiration are necessarily confined to that painstaking iterative line-by-line process of real writing. When you are simply prompting and editing, you will fill the page (and it might even sound like “you”), but you will not have that delightful experience of encountering something unexpected along the way to filling it.
There's nothing stopping you from doing that with an LLM. I get more insights refining a draft through prompts than I ever did writing because there's more of it. The end stage of that process rarely sees the light of day because the artifact wasn't the point.
For writing as thinking with trouble starting from scratch, LLMs are the most important technology to emerge in my lifetime. Microblogging filled that gap in a way, but it had too many downsides.