Mildly Infuriating

Which is still stupid as a single quote is an apostrophe. Quotation marks of any kind didn't really exist prior to the creation of the printing press (this is also why there are many many local variants). There were several marks that were used to emphasize or highlight passages, but not to directly mark something as a quotation. When printers found themselves in need of a character they didn't have they re-used existing characters (since characters were literally hunks of metal and they couldn't exactly go out and whittle a new one).

For apostrophe they just flipped a , upside down, and thus the apostrophe was born (a similar mark used to denote where something was omitted was used in writing, so the apostrophe did exist prior to that point, but it was written more in the style of a carat above the word typically).

When they needed a way to mark quoted text different printers used different characters. For some they re-used the same trick as they used for apostrophe and just used upside down commas and thus the single quote was born. Others did the same, but in order to differentiate it from the apostrophe they double it up, hence the " character is literally a double upside down apostrophe. Some used either single <> or double << >> brackets to denote quotations. Some use a comma and apostrophe E.G. ,a quote' or doubled it E.G. ,,another quote'' (N.B. it looks like the comment renderer on here is eating the double , replacing it with a single , and possibly replacing the double ' with a single " character). It was all down to whatever the local printers had available and felt was appropriate.

Hence getting bent out of shape about if a ' is an apostrophe or a single quote is utterly stupid, it's both as they're literally the same character.