[eigengrau]

> in the current century fonts handle that

Except that they can’t, because (due to the limitations of ASCII), U+0027 had an overloaded meaning, seeing that the character had to cover both opening and closing quotes (as well as being used as a prime tick). Which is why pretty much every font I’ve seen has a straight glyph at U+0027, whereas the glyph at U+2019 is the one you’d usually want for an apostrophe. You can also observe that word processors follow the Unicode standard in this regard. E.g., after typing “they're” into Libre Office, once you copy-paste it, you’ll see that the ASCII single quote has turned into U+2019.