Earlier quoted context omitted.
Technically speaking, no, HN doesn't render any titles. Your browser is displaying U+1F97A, which is sent over-the-wire as the bytes \xF0\x9F\xA5\xBA (UTF-8 encoding).
By "render" they probably meant "didn't strip"; HN will strip emoji from comments/titles, generally. E.g., the emoji of the article: "" but I suspect there won't be anything between the quotes. (An exception was made for the title, in this case; dang mentions that in a comment in the comments here.)
Yes, this is what I meant.