I think the interest has been low because very few documents survive in these encodings, and even fewer documents using not-already-encoded symbols.
In my opinion, this is a good use of the Private Use Area among a very small group of people. See also https://en.wikipedia.org/wiki/ConScript_Unicode_Registry Best regards, markus PS: I had a ZX 81, then a Commodore 64, then an Atari ST, and at school used a Commodore PET...
