> What I meant is that you don't expect PNG or JPEG images to be created in a way that the parser needs to run a complex process to reconstruct the bits that are broken and interpret what you meant to say.

So what you meant is neither what you wrote, nor what you advocate for?

because in case you have forgotten here is what you advocate for:

> Pages that don't conform with the specification won't be rendered.

That is not how image rendering in browsers works. That is how XHTML does not work.

> Perhaps a better example is a C program being compiled into an executable.

It's not a better example, because it's a completely different and unrelated use case: C programs are usually not dynamically generated, and even when they are the person who compiles the code is usually either the person who wrote it or a person who has ways to fix it or report errors.

Not so when trying to read a web random page on the web.

> I don't propose humans to write this format directly (although it should be human readable)

Approximately nobody wrote xhtml by hand, didn't save it.

This is also a nonsensical constraint-set on its face, there is no point to a human readable format which is not human writeable.

> The objective is to enforce tools that make the transformation to produce a strictly conformant document.

Ah, an open and non-monopolizable format which can only be written via an official toolchain.

> Having a context-free grammar allows simple and fast parsing tools that can process your document in a similar way that you can query or manipulate a JSON^H^H^H^HXML file with tools like jq^H^Hxmlstarlet because the grammar is simple and strict.

None of which seems of any use to a format which pretends to human production and consumption. JSON is an interchange format between machines.