markdown tried very hard to encode conventions that were already used in Usenet, email, and other text media
For those of you who weren't there:
*bold*
_underline_
~strikethrough~
/italics/
> Quotation
- list
- list
- list
I've been using these for almost half a century. They're much easier and more intuitive than Markdown. I see no compelling reason to change.One problem with the /italics/ form is that it's not convenient when writing about filesystem paths (though I do like its visual indication of slanting).
But Usenet style didn't have a trendy name, an 'inventor' or Github stars. So it didn't exist.
Your quotation and list syntax should work out of the box in most Markdown flavors (HN has a very non-standard and crippled version - basically nothing other than italics, paragraphs, and code/preformatting works.)
Strikethrough and bold are doubled to avoid common ambiguities. Your underline should technically work, but it comes out as an <em> (emphasis) tag, which is rendered as italics in most browsers.