But yes, that's the future I'd like to see. Browsers only have a WASM engine, and provide a JS->WASM compiler client-side for backwards compatibility.
You'll need most of a runtime anyway, since it provides much more than GC.
Obviously if we're trying to run a full JVM or CLR in WebAssembly, that will cause problems, but C# and F# both have compile-to-js targets that would likely just get faster.
Sure it does. And the myriad of languages that pop up to support WASM will work infinitely better. ES6 was a huge step forward, but it's still a long way from a real language like C#.
I suspect Javascript development will always be a thing, but that front end development will fracture into multiple different languages and runtimes as full WASM support comes online.
While I can agree that C# has tons of language features that make it more powerful than JavaScript, I take issue with the idea that those features are the defining characteristic of a "real" language. I think there are many reasons to choose C# over JS, but there are also a non-trivial of reasons to make the opposite choice.