That was the intention of XHTML 2.0.

Header levels would have been derived from the document structure.

    <section>
        <h>Hacker News/h>
        <section>
            <h>Guidelines</h>
        </section>
        <section>
            <h>FAQ</h>
            <section>
                <h>...</h>
            </section>
        </section>
    </section>