Reminder: LibreOffice is a more than viable alternative.
Or even better, stop doing paper format documents on your computer. It creates data silos and often isn’t really accessible either. Who (except maybe governments) does still print stuff?
Organize your data relational. Tools like NocoDB or Baserow let you do this pretty easily and in a privacy friendly manner (self hosted).
oh, there are certainly better fits than Word and it’s clones for different tasks.
but let’s say you need to write a 50 to 100 page narrative document structured into chapters/sections, with illustrations. Curious about your approach to that
EDIT: lets also say you’re not in CS or academia and emacs/TeX are out.
Markdown. Obsidian, Logseq, or even Notion or Coda.
Markdown is plain and easily parsable by pretty much anything.