@stefanct not sure why your comment, if you work on a project that has such strict line length limits then that should encourage you to contribute an option to set breaking on newly opened files.
But most of Geany use-cases are about coding, where line breaking is not wanted, so thats probably why its never been done.
This is not saying it should not be done, but possibly why others who:
1. do not have such strict limits, and/or 2. use languages where random line breaks may be significant, and/or 3. just find it annoying, and/or 4. are happy with the indication from the long line to prompt them to make a line break at an appropriate place in accordance with their projects formatting rules, not randomly
have not done it. And it is still not done two years later.