But seriously, this is a good listing of pros and cons, and it is a pity not more experiences are shared. Commercial products usually pay good attention to the docs, but esp. FOSS projects are often severely under-documented. Model may be different here as often the single dev is the documenter too (and hates that chore). I tried Readme Driven Development [0] for a while, but found it still resource-intensive to keep things up-to-date. For single devs, small teams the Diátaxis framework [1] is helpful to organize and makes the task a bit lighter.
[0] https://tom.preston-werner.com/2010/08/23/readme-driven-deve...