>> the main reason why no ones does this is because you would be missing the most useful aspect of React which is compatibility and consistency with the rest of the React ecosystem. So you cannot separate React from its ecosystem. All this complexity has become tightly intertwined.
This is just plain wrong. Firstly using JSX or not will have 0 impact on compatibility with other libraries in the ecosystem because they are not coded against JSX they are coded against what JSX is compiled down to. The main reason people use JSX is because people like it.
Also you say the complexity has become intertwined but I don't hear any examples of how that is the case?
I disagree with this. Everyone claims that you can use React without JSX but no one does it. Aside from ugliness, the main reason why no ones does this is because you would be missing the most useful aspect of React which is compatibility and consistency with the rest of the React ecosystem. So you cannot separate React from its ecosystem. All this complexity has become tightly intertwined.
If you use VueJS without a bundler (which is actually feasible), you will be surprised how much simpler and elegant the whole development experience is. Once HTTP servers start supporting static push of scripts, we will not even need bundling in production.