> I don't think <strong> meant <em> but more so
I guess it was an HTML 4 thing, the standard at the time of Markdown, https://www.w3.org/TR/html401/struct/text.html#h-9.2.1
<em>: emphasis.
<strong>: stronger emphasis.
I see that HTML 5 has tweaked their descriptions, https://html.spec.whatwg.org/multipage/text-level-semantics....
<em>: stress emphasis
<strong>: strong importance, seriousness, or urgency