WASM! Being able to write your own language that compiles to something that can run almost at native speed in the browser (pretty much without js) feels like a magical watershed moment.
Can I ask what kind of languages you're thinking of compiling? I was pretty excited about WASM too, until I realized it was bring-your-own-GC (which makes sense in retrospect I suppose), and libgc's WASM support had heavily atrophied last time I tried it (last year), such that it was freeing memory that was still in use(!!). If there's a high-quality GC for WASM you've used, I'd love to know about it for my own use!
As you pointed out true GC is currently postponed, so no long running processes yet. The hope is to get the language finalized just in time when all wasm 2 features become standardized
I'm mostly interested in the obfuscation advantage that WASM provides. Being able to encrypt the whole thing and embed it in the web page to avoid using fetch is allowing me to deploy apps in a more secure way.