What if:

1. JS supports JSX literals so

   let elDef = <div id="some">Text</div>;

will be compiled into

   let elDef = ["div", {id:"some"}, ["Text"]];

2. We extend DOM API to accept such constructs:

   element.append(elDef);  // same thing as element.append("<div id=some>Text</div>");
   element.prepend(elDef); // ditto
   element.patch(elDef);   // patch element's DOM by elDef

3. Add appropriate events: componentDidMount, componentWillUnmount, etc. for cases when tag in JSX (uppercased) resolves to a class or function.

4. Add render() support. A method that generates tree of elDef's. It gets called by append(),prepend() and patch().

And we will get native React implementation. This will be quite useful and allowed to marry React alike approach with WebComponents into single mechanism.

1...4 is how it is implemented in my Sciter as the Reactor thing, see: https://docs.sciter.com/docs/Reactor/