Not so sure. JSX is already a transpilation language. Why target a language that's only supported as an input language for other compilers? I don't think this is an LLVM-type scenario.
As an example, Solid's JSX compiler changes multiple times in a year. It's better to target JSX than the compiled form. There are also many JSX compilers. (Even React ships with at least two.)
Civet's futuristic JSX compiles to actual spec-compliant JSX, to it's compatible with all forms of JSX, including React, Solid, etc. We'd like to support other DSLs like Astro and Svelte as well.