I suspect that if some accidents of history hadn't left JS as the only language you can use to script a Web browser, it would have died off long ago.
There is, however, quite a bit you can do in it. TeX has been compiled to wasm[1], it's about 600kb uncompressed 90k compressed (the memory image with latex loaded is about 6MB compressed though - latex is a beast). I think anything computationally intensive would be a good candidate for wasm (it has int64).
Anyway, on practice all that means is a bit of lost performance on the DOM interaction. It's a big deal if you do a react-like framework, but the DOM has bad performance anyway, so people tend to not create react-like frameworks.
Everything was mucked up well into the 2010s with everyone chasing IE compatibility. And not even 3 years later, Chrome had taken over the world. That's a really brief window for anything to happen.