Is it me or did that medium article make a big stink about using system fonts, but it sits on a page that has a font specified as medium-content-sans-serif-font

Is it me or did that medium article make a big stink about using system fonts, but it sits on a page that has a font specified as medium-content-sans-serif-font which isn't even a URL-ed font. It is base-64-ed into the css file so the font is not even cacheable across sites if other people bothered to use it.