And, he didn't even touch on the horror that is EBCDIC. Once you've had to touch that, the idea of "code point" for a character is something you can't ignore, hoping that things just work "most of the time" -- ASCII A != EBCDIC A.
It's easier to read text on punchcards in EBCDIC of whatever variation, though.
(disclosure: I once worked at a company that made tools to port code and data from IBM minicomputers to Unix & MS platforms, and also at the largest [format,] print & mail shop in the US)