I’m specifically objecting because of the text “I'm creating a blog platform using this concept” and what else the author is saying here. As a technical demonstration, it’s fine—various people don’t realise you can do things like this, and I’m all in favour of showing people these sorts of things, as it
does get people thinking in interesting ways. But the author seems to think that this is a
good idea, which I’m afraid it’s just not, so I can’t mince words—though perhaps I have expressed myself a bit more strongly than is seemly (thank you for pulling me up on that).
Of React (and its ilk: React was by no means the first project along these lines; as an example, I can think of having hit a couple of full JS-required Knockout sites well before React was a thing, where they would have been better as prerendered HTML), I’m not saying that history was rewritten to say it had a place from the beginning, but rather that there was a place for it from the beginning: that there is a certain type of app where there are very substantial benefits for the user in doing at least some parts on the client side (that was where the jQuery style of progressive enhancement started, and then things like Backbone steadily expanded it), and then that architecturally there are substantial benefits to going all in on client-side rendering if you need this sort of enhancement (this was what Knockout tended towards, and what ExtJS and React more fully realised)—but that this had costs, too, in that it broke the traditional model, making life harder for all kinds of tooling and making pages heavier, so that it shouldn’t be used everywhere.
React was not initially intended as a way to write web sites, but rather web apps. It’s an important distinction. For apps like Facebook and Twitter, the advantages of server-side rendering were not so applicable, and the benefits of full client-side rendering more marked. Unfortunately, the SPA craze grew further, and people liked using one tool everywhere, and so it became more and more common to use React in places where it was inappropriate at the time; until finally tooling like search engines caved on the whole JavaScript thing.
I still don’t like how often I find normal websites depending on JavaScript for fundamental rendering (it may not surprise you to discover that I browse with JavaScript disabled by default—mostly for performance and minimisation of annoyances), but at least React has purpose and some advantages, and has done from the start.
Meanwhile, this thing here doesn’t get you any of the benefits of client-side rendering (things like lighter and faster subsequent page loads and transitions, by using AJAX and semantic knowledge), but does carry all of the costs of client-side rendering: poorer performance, and making life harder for tooling of all kinds.