Are there any numbers comparing pre-rendered React versus React communicating with a JSON Api?
It seems to put a lot more stress on the server which can neglect the (theoritical) speed improvements
Not sure, but the time cost is the latency of loading an almost-empty index.html, loading and parsing your app, _then_ it starts running and hopefully fast doing some API requests and then it's off and good to go. Subsequent JSON-API-requests-and-then-rerenders should be pretty fast indeed, but those aren't the point :)
You want to server-side render React apps so that while all that happens, the app already works.
You want to server-side render React apps so that while all that happens, the app already works.