https://futuretextpublishing.com/ --> books vol 1-5

And what comes to original article, there is no "text [systems]" (or there is, like there are "number [systems]", just made up). "Text" like this very thing you are reading is 2D drawing. There are no character glyphs of any kind (latin, logograms etc.) defined by universe*, they are human invented and stored/interpreted at human collective level. Computers don't know anything about text, only "numbers" of some bit width, and with those numbers a system must be created that can map some number representation to some drawing in some method (e.g. with bitmap). Also there is a lot of difference between formal/executable and natural human languages. Anyways, it's not a about some text format/encoding, it's the human/computer defined/interpreted non-linguistical meaning behind it (Wittgenstein).

* DNA/RNA can be one such "universal character glyph/string", as the "textual" information is physically constructed and interpreted.