I've been looking at ProseMirror (mostly through tiptap2, which seems to wrangle it effectively) but taking the jump is daunting. I'd be interested in others' experiences.
Overall, it's the only tool I found that makes it as easy as possible to create a good writing/editing experience but it's a hard easy.
The docs are thoughtful. There's an up-front learning curve to understand the architecture. When doing highly customized things, I referred to the source when needed.
For standard rich text, there are a lot of options. Prosemirror shines when you want to build on it as a platform.
I ended up abandoning the project but wrote a short introduction here which might help you get started.
That said, text editing in the browser is indeed a nightmare, so it's hard to fault anyone trying to make it easier.
Quill has `getSemanticHTML()` which is great for my implementation.
PM is great, but expansive and overpowered for my needs.