Especially if there was major momentum of people writing their web applications with wasm, there would be a reason to eventually get that massive undertaking of creating the ABI for that working. Then all those applications could just recompile to make use of this new hypothetically faster API. The bigger issue here is that it just doesn't make any sense to write frontend code in rust or go or whatever in the first place.
The whole js ecosystem evolved to become a damn good environment to write UIs with, people don't know the massive complexity this environment evolved to solve over decades.
I feel like this is asking for a jquery for WASM. All you need are css selectors and verbs. The selector is a choke point that keeps you from having to create a concrete object on both sides of the FFI. And the fact that jquery is built for bulk operations would also be a feature you’d want to preserve for performance reasons.
The whole js ecosystem evolved to become a damn good environment to write UIs with, people don't know the massive complexity this environment evolved to solve over decades.