> the browser dev tools already have to include a "prettify" option. Moving to a binary protocol would turn that into "decompile" and make it mandatory, but it effectively already is.
This will be a legal problem. At least in my jurisdiction, transforming source code (which is what prettifying is) is not subject to legal restrictions, but decompiling binary machine code into readable source code is forbidden by copyright law. (For the same reason, I'm concerned about WASM.)
I disagree with that. Using binary formats to exchange data between programs doesn't preclude using textual formats at the human/machine boundary. Yes, "view source" needs to be more intelligent than just displaying raw bytes, but that is already the case with today's textual formats. Everything is minified and obfuscated, so the browser dev tools already have to include a "prettify" option. Moving to a binary protocol would turn that into "decompile" and make it mandatory, but it effectively already is.
Requiring a compiler to author and distribute a web page is no different than requiring a web server or a CGI framework or the JS-to-JS transpiler du jour. It adds another step in the pipeline that needs to be automated away for casual users, but that's manageable. Even if the web world moves to binary formats (as WebAssembly seems to indicate), your one-click hosting provider can still let you work with plain HTML/CSS/JS and abstract the rest; just like it abstracts DNS/HTTP/caching/whatever.