> In fact, the complexity of Chat Messages and Notifications synchronisation is one of the prime reasons why React exists.

SSE is perfect for chat/notifications and is a lot simpler than syncing. The server pushes updates to the client doesn't require a sync. SSE is also more performant since it can keep the connection open. The example below is on a $10 vps last I heard.

https://data-star.dev/examples/dbmon