I use it for my home computer emulation stuff, the same code also compiles to minimal native applications (but with WASM there's not much of a point except during development and debugging - still it's good to have a "native fallback"):

Also see: https://github.com/floooh/sokol and https://floooh.github.io/sokol-html5/index.html.

(e.g. for me it's a way to easily get my C/C++ cross-platform hobby stuff to people without requiring them having to jump through the hoops of downloading and running an untrusted native executable or messing around with C/C++ toolchains and build systems to build the stuff locally).

PS: WASM in the browser is also a good watchdog which punishes you heavily if your code gets to bloated ;)