This is probably before your time, but in the 1980s, very large mainframe applications were written in assembly language. Doesn’t mean it wasn’t painful. Doesn’t mean it was a safe, reliable way to develop applications.
Today, most companies would avoid using assembly language.
The web development field is an odd one. People in this space have deluded themselves into thinking that JS is a good programming language. That’s why front-end programming is way overengineered and needlessly complicated. React is a fucking mess. So is the toolchain.
Just because you can shoehorn JS into such a large task doesn’t impress me. JS is today’s mainframe assembly language.