This is huge! It’d be so cool to see the JS community get into rust! Maybe someone needs to write a rust-based jQuery or react?
WASM isn’t really great for interfacing with the DOM. You can farm out expensive computations to WASM (“calculate this” / “parse this” / “do some string operations”) but doing stuff with tight DOM work will not help performance much (if at all; I’d expect it to slow down), and will have questionable benefits as to typesafety (TypeScript is a better way to get this working well)
DOM manipulation isn’t slow because JS is slow, it’s slow because it’s inherently slow – it retriggers restyles and relayouts and a lot of other computations in the browser. Rust can’t help with that.