I agree - I think JSX does what templating languages have been trying to do for years.
That being said, solid is hardly the only one out there competing that can use JSX:
- https://github.com/vuejs/babel-plugin-jsx
- https://mithril.js.org/jsx.html
- https://preactjs.com/guide/v10/getting-started#setting-up-js...
I think people are starting to see the power of it when it's used in a functional manner (rather than early class-based components). A lot of alternate template libraries are only minorly different in syntax and use different styles of interop to handle the crossover. I think .svelte and .riot are fairly close, while still being somewhat html-like, rather than JS first.