I would consider that the worst scenario. If each website was its own binary application it would undo the open source aspect of websites (even though that's only partly true today due to all the obscured javascript). But maybe that would actually be desirable for all companies which rely on advertising revenue and want to prevent any modification of their web content (such as removal of ads). It'll be interesting to see how the web develops in the future. WebAssembly definitely seems to give more control to the author.