In writer there is Menubar -> View -> Scrollbars -> show/hide Vertical/Horizontal Scrollbar. To cleanup the UI and cause it's not that importend for Draw and Impress it would be nice to have this options also in this sd apps.
I see no benefit in putting developer time in such a new feature.
I don't see an developer will work on it.
what I see is that after each release and after that much effort the design team put into new icons, ... it's always the same. LibreOffice look old and from the 90's
LibreOffice Online has scrollbars visible only when hover or while scrolling.
Whether scrollbars are shown should be up to the OS/DE. In case of LOOL it's the browser that make them disappear. So my take is to remove the option from Writer too. But for sake of consistency I agree with adding it to other modules (except Calc of course).