Comment by kbolino

IMO <em> is a terrible example.

For ca. ten years, the advice was to pointlessly "replace <i> with <em> and <b> with <strong>" and it utterly screwed over most new web developers' understanding of semantic tags. There are many reasons to use italics (and they vary between languages) but "emphasis" is just one of them, and none of the others ever materialized as tags.

It would have been far better to have recommended <i class="emphasis"> and <i class="media-title"> and <i class="snarky-aside"> etc. than to have added the <em> tag and said "just use it instead of <i>".