1) It cannot be easily embedded, ie. as a field in a form. Apparently it's meant (UI-wise at least) as a full-screen editor and has lots of dependencies of its own, including React.
2) AGPLv3 license is a killer. Means that any work that links to the library should be opensourced. Despite some people interpreting it differently, it would be risky for a consumer product to ship making use of this library.