Here's a relevant recent EU court case of a person arguing with their bank that their name should be represented properly including the accented 'é', as the GDPR asserts a right to have mistakes of personal data corrected. The bank argued that it's impossible due to a legacy system using EBCDIC encoding and would be expensive to change. The appeals court affirmed that the customer has the right to get mistakes in their personal data corrected, and it is the duty of the bank to do so even if it is expensive.
I once did it, encoded UTF-8 text in a legacy text because the system interface didn't support unicode, and decoded on the other end. Used • prefix as a marker of encoded string... now that I think about it, it could be just old good BOM. MIME standard also has extensive experience in packing arbitrary data in 7-bit clean text.
This is an insanely nightmarish precedent. We need to take computer systems less seriously. In a human-interface world, these issues are avoided thanks to simple human intuition.
https://gdprhub.eu/index.php?title=Court_of_Appeal_of_Brusse...