Are you really saying that non-ASCII is notation and ASCII is not? When I read your first comment, I understood it to mean that better notation is better than worse notation.
Notation is obviously a shorthand for "sensible notation" or even "better notation" there, because obviously just about anything can be notation. Including laying out pebbles on a beach.
But further than that, I don't know.
Some people hold prejudice against parentheses and prefix notation, for others it's ASCII...
J uses . and : as modifiers to a base operator to create a pretty big set of primitives. See https://code.jsoftware.com/wiki/NuVoc
I mean, in a fixed-width font (as people tend to use for programming) it's literally twice as long. That adds up.
This is less true since APL has begun integrating J semantics and operators, but still..