What I don't understand, we have a whole bunch of semantic HTML elements for years now (<main>, <section>, <header>, etc.) and no need for <div class="main"> anymore, but they don't get used very often.
1) There's no real world benefit to using these elements, in any easily demonstrable way (maybe there's some sort of tiny accessibility or SEO advantage, but it's fractional in comparison with, say, just using H1/H2/H3 correctly), which mostly leaves them as an exercise in academic purity.
2) The definitions are really woolly and require far too much thought, especially given the previous reason. Why bother debating whether something is a SECTION or an ARTICLE or a MAIN when you can just use a DIV, with whatever probably overly specific `class` you were going to use anyway, and it will still work in exactly the same way?
<section>, <header> and <footer> are not too uncommon.
<article> is by far the most used, and is also put to genuine use in parsing by things such as Firefox/Safari's Reader views and other such tools. <section> gets used similarly by some parsers I think, though I've no direct examples off the top of my head.
For the high-level layout elements it's not so bad, but the <i> element being defined as indicating things such as "taxonomic designation, technical terms, foreign idioms, transliterations, thoughts, ship names, or dream sequences" renders it basically pointless. The HTML spec encourages you to use a class attribute to identify why <i> is being used, but then you might as well use <span>.
Most browsers - maybe all modern browsers - actually accept made-up elements and let you apply CSS to them. There's no good reason - other than compatibility - why authors shouldn't create ad-hoc elements - e.g. <dream> or <tabs> - that match up with the true semantics of the content.
Some of the most common layout tags I see are: header, main, footer, section, article, aside, nav
Other things can have <footer> tags too. I've seen plenty of <footer> elements inside <blockquote> tags!