No one argues that having automatic bullet or numbered lists would be a worthwhile addition. It's on the wish-list. It will get done at some point.

But I'd argue that the point about HTML structure is not valid. The tags only exist because back-along you created websites by hand, hacking the HTML and the only way to add a heading (or something as simple as italic) was by adding embedded tag commands. They only exist through a dint of history. It was the exactly same with old word processors, before they went WYSIWYG. Same with DTP programs, but how many people use TeX now? WYSIWYG design tools have made the whole manual mark-up redundant.

There is no value in having HTML 'structure'. Search engines do not use it - they care only about the text (some people mistakenly believe, and spread the myth, that is matters to search engines - it does not). All they care about is that text. By all accounts Google doesn't even look at very specific metadata, the keywords metatag, so they are not going to pay attention to <H1>. There is no value in the 'vocabulary of HTML' as you put it.

So in fact as and when we implement easy bullet lists we probably will not do it with the <li> tag even, but our own way so that designers have accurate, predictable, WYSIWYG lists. I can see little value in using the <li> when what people really care about is that the lists looks right, and exactly as they intend on all browsers.

As to the 'accessibility' point this is mute point as all mainstream browsers have moved to full page zoom where everything on the page zooms (like in Xara). This is a better solution for everyone, blind or not, because then everything gets bigger in proportion and you can zoom into graphics, photos and text. And designers are happy because their page remains completely intact as intended, just bigger.

So the only browser that do not implement full page zoom (Chrome and Safari) are switching to it real soon now. Problem solved.