[mrweasel]

>If yes, why not use "vanilla" js?

Isn't that like asking why jQuery exists?

Personally I still believe that JavaScript and HTML should be separate, like HTML and CSS. I know that might make sound old, but I really dislike having a template language embedded in my JavaScript library, and as a result I end up disliking most of the newer frameworks.

I know jQuery, the documentation is good, it's easy to get help, and it makes sense to me in a way React, Angular and others frameworks do not.

Yeah, I could use plain JavaScript, I could also just use Python and not have a Django or Flask dependency. It's just easier and more productive to take the dependency.

[Guillaume86]

I can relate to this idea, but I gave a try to react and I changed my position:

Here's why IMO react is not actually mixing the two: HTML is just the serialized form of the DOM, your browser reads it, transforms it the a DOM tree before rendering it.

With react, you interact with the DOM (indirectly via a virtual DOM API), so you manipulate javascript objects, you only do javascript. JSX is just syntaxic sugar over that API, because deep nesting is easier to read with XMLish syntax. JSX is not a templating language (that outputs a string).