You said "putting functionality in the wrong places".
The font system does not have any such functionality as z80 disassembly. It has generic functionality for generating glyphs.
If there are any normal human written languages that benefit from the functionality to generate modified glyphs dynamically based on content and context rules, then the functionality is not misplaced.
Of course it’s useful for human languages. Using it to disassemble Z80 hex dumps is what I have mostly aesthetic objections against. It’s both fascinating that it can be done and horrifying that someone actually did it.
The font system does not have any such functionality as z80 disassembly. It has generic functionality for generating glyphs.
If there are any normal human written languages that benefit from the functionality to generate modified glyphs dynamically based on content and context rules, then the functionality is not misplaced.