Scheme language is very well-suited for producing websites, I've been doing that for several months with decent results. But unless I missed information, I think you're right that has nothing to do with WebAssembly. However I know Scheme->wasm compilers exist if unsure of their status.

Of course many languages can be used to create or serve websites. If language doesn't matter, then why not Scheme? It's at least as capable as the languages mentioned. OTOH much less is written about Scheme vs. more "mainstream" languages. Maybe that does make a difference.