I think every sentence in this post is more or less wrong. Also, we do not want to introduce non-ascii glyphs into programming languages - APL is about the only time this has been tried and (merits of the language aside) it was hardly a success.
Fortress is a much less popular language (perhaps, to be accurate, it should be described as a failed experiment) which was intended to permit the same thing. Offering an ASCII, Unicode, and prettified presentation of code.
There are quite a few other languages which support Unicode characters, though most of those don't aim for the same symbol heavy presentation of mathematical code.
However, the submitted article is not about programming languages so your post and this response are both off-topic.
https://en.wikipedia.org/wiki/Space-cadet_keyboard
to make a comeback.
Is it possible that you misinterpreted this as a post about << and >> in code rather than their usage in mathematics?
It also has ways to write the same things in ascii, but it is a fair bit less convenient to read.