As a non-expert outsider, I thought that was the promise of React since the early days? Isn't there already server side rendering?

What you describe, a PHP style server rendering of mostly static HTML, with small bits of JavaScript for interactivity, sounds great. But will that actually be possible?

I'm really really sick of web apps and mobile apps that flash the "no content here" version of widgets while they wait for data to be loaded. It's the very very worst sort of user experience.