Nah, it’s well and truly in production now. There are new features needed to support some languages better, and closer integration with the DOM may arguably be

Nah, it’s well and truly in production now. There are new features needed to support some languages better, and closer integration with the DOM may arguably be desirable, but my understanding is that it’s at the point where heavy lifting can be done in wasm, with automatically generated JS stubs. I might be wrong (not a front end specialist) but ISTM that a native TS implementation built today would more likely be a compiler to WASM than try to become a first class browser language. And anyway, direct browser support for TS would take as long as WASM has taken to gain broad support.