You've posted a lot of negative comments but seem to not understand or have any experience with CRDTs. The whole point is that state modifications on the data

You've posted a lot of negative comments but seem to not understand or have any experience with CRDTs. The whole point is that state modifications on the data structure by separate parties can converge to a final representation without any coordination. The math behind it is proven, however turning mathematical set-theory into a usable JSON interface is where the problem occurs. A free-form JSON doc can't be completely supported but these kind of edge-cases around property updates are easily handled by using an array to hold modifications instead. CRDTs even have state-based and operation-based usage models to handle different scenarios, and then there's an entirely separate but parallel tech called operational transforms for other situations. All of this is not only well-studied but widely used in many collaborative applications (eg: Google Docs).