[mweidner]

Many projects use Yjs for its collaborative rich-text editing (e.g. Linear: https://x.com/artman/status/1733419888654291102). Yjs makes this easy by providing "bindings" to various rich-text editor GUIs, which sync between the editor's internal data structures and Yjs - something that involves a lot of detail work. Automerge's rich-text support is more recent (~last year), and so far they only have one editor binding (ProseMirror), so Yjs is naturally more popular here.

For non-text collaboration, there is a more crowded "market", because it is an easier problem to solve - at least when your app has a central server. Tools range from hosted platforms like Firebase RTDB to DIY solutions like Figma's (https://www.figma.com/blog/how-figmas-multiplayer-technology...). Meanwhile, Automerge's target niche is decentralized collaborative apps, which are rarer.