You should pivot, be the Frame.io, Figma, Framer, etc. of writing tools.
You could do it... I'd help you if you want.
I'm also a web developer, heavy front-end, UX dev, etc.
I think you could benefit from an overhaul with focused UX and focus on collaboration phases that real indie authors really need. A bigger focus on external integrations needs implemented as well.
Exporting needs to be a huge focus as well.