If we accepted the validity of this argument, then literally everything that can be represented by a computer can be referred to as text.
It renders the term "text" effectively meaningless.
To be fair, in Lilypond's case, it is an ASCII interface that renders to sheet music (kind of like openSCAD).
To be fair, in Lilypond's case, it is an ASCII interface that renders to sheet music (kind of like openSCAD).