Some of us find the language highly productive, and extremely accurate in its usage in many different spaces.

In terms of webassembly, there is a sweet spot for Rust, which is in speeding up CPU bound JS routines. There is a project, wasm-bindgen, to make building these high performance pieces and injecting them into JS easy.

Some of us even want to see it grow as an alternative language for full web development. There are a few projects that aim to make this easy (compiling to wasm): stdweb, cargo-web, js-sys. It’s already a fully capable language capable of targeting the web.

The features you get for this that many of us appreciate: no garbage collector (ie bounded memory usage), strict error checking, strongly typed null checks, an amazing type system, etc. Productivity means different things to different people.

Here's an example: I wanted to have decent hashing performance in JavaScript (large file uploads protected against bitrot). There are a hodgepodge of different JavaScript libraries with inconsistent algorithm support and performance characteristics; SubtleCrypto is becoming more standard but has limited algorithm support and doesn't support efficient operations on large inputs.

With https://github.com/acdha/wasm-hashing I was able to use the high-quality Rust hashing system to support all of the different algorithms I needed with a consistent interface and performance was actually competitive with or better than the browsers' native SubtleCrypto implementation.

That's a really nice capability to have in your back pocket, especially since it comes with Rust's usual assistance for code-quality.