Our entire development team works on and codes the pages, applying web standards and best practice, starting with structuring all the content.
At the design stage, the different levels of headings (h1, h2, h3, h4, h5, sometimes more), buttons (primary, secondary, tertiary) and text are created and designed for integration.
The tools we then use to build websites (content blocks, for example) help to structure and hierarchise all the encoded content.
So the hierarchy exists and is used, and this is reflected in the code - for assistants and engines among others, which also helps the SEO of the sites created.
The best practice of structuring content is a subject that is widely discussed with our customers throughout the projects, from general hierarchisation (thinking about an architecture, planning content for the different pages and sections), to individual pages (prioritising, presenting and prioritising content on a page), via day-to-day production (thinking about sub-headings, breaks, airing out the text with a structure that allows it to be read quickly and clearly, etc.).
In other words, use the editing tools available to make reading easier for people and robots alike, to the benefit of the site's performance and therefore that of its owners.
We could probably insist even more on the use of these tools, the importance of limiting yourself to one h1 per page, and the impact this has on site accessibility, among other things.