Well because I can have upper and lowercase letters in the same font. Aa. Upper and lower cases have different significance, ie. starting letters for honourifics and proper nouns. Unless you want to take a very unconventional view that uppercase is simply a different font from lowercase, which is not how anyone else in the world uses the word.
> Upper and lower cases have different significance
Yes, that's why they're a good example of assigning semantic significance to the font that something is written in.
> Well because I can have upper and lowercase letters in the same font.
What do you think that means?
Try this one: I can have Arial and Calibri letters in the same font.
Where a 'font' is a data file used by word processors to render ASCII or Unicode, it's just as true.
If you think a 'font' means something other than that, what is it, and how does your definition preserve the idea that a capital A and a lowercase a are distinct in some dimension that isn't their 'font'?
