Embedded development, high critical systems, mobile platforms (the choice isn't really there), game consoles.
It is mostly C or C++, Swift/Objective-C, Java/Kotlin.
There are other alternatives you might want to point out, notice however they need integration layers, leaky ones, some yak shaving not much different than targeting WebAssembly, and still having to talk to JavaScript.
there is no alternative to the web and within the web there are no alternative languages.
for embedded, you have options, no? and I don't mean glue: rust. quick Google says Ada and assembly.
Assembly is not an option per se, some embedded devices like PIC, usually still have to be written in Assembly.
Yes you might have Rust, Ada, Pascal, Basic as alternative, however the choice only goes as far as the CPU vendor SDK supports alternative toolchains, or the whole certification process allows for a choice (hence why Ferrocene exists now).
So if in the end you still have an option to go outside the trailed path, it usually means yak shaving to make your toolchain work on the target, or have bindings to the official SDK, instead of actually solving the problem, had you started with the official SDK languages.
the reason why I didnt is because I despise JavaScript and was hoping that webassembly would give an alternative. which never became an alternative.
with embedded you are arguing for my point. you say sometimes there are alternatives (maybe depending on the platform). sometimes not. you can change platforms as well. that's fine. sometimes is very much different from none. and we have none for the web.