There are sites where accessibility isn't much of a concern (esp things like games) or where it would be easily handled (eg. an image aggregator). For the rest,

There are sites where accessibility isn't much of a concern (esp things like games) or where it would be easily handled (eg. an image aggregator). For the rest, it seems inevitable that another (probably not-quite-compatible) accessibility layer gets built on top (for example, using the Qt accessibility model when compiling Qt into a canvas). Overall though, I think wasm shouldn't be replacing HTML/JS.