We are comparing different things.

I am comparing expressing information in semantic HTML or in Markdown. HTML doesn't bloat it much, and it is easier to work with (programmatically in python, ts, go, java, etc.; including parsing and composing and formatting). I am not talking about web apps, which commonly have more "app" than "information".

And the ratio is really closer to 1.1x tokens than 1.2x, unless the information you are expressing is highly structured. Typically 1 structural element (html tag, markdown marks such as ###) ends up being each 1 token. HTML often has the matching closing tag, and that is really what the difference in number of tokens boils down to. Feel free to run your own tests and compare (I ran a few and it was within 1.09-1.14x).