It has some even more fundamental bugs with PDF. Concatenating transformation matrices with negative scaling (i.e to flip the coordinate system you're drawing in) is completely broken in Preview and Safari. It's completely conformant according to the PDF standard.

Obviously prints fine and chrome/firefox or Windows don't have any issues with it. Obviously Adobe has no issue with it.

But here it is staying broken for years, because you can't explain to mac users that Apple is the one that made the mistake if they preview things your tool generates and they look broken. So devs just "fix" their PDFs to be bug compatible with Apples version.