But many, perhaps most, parsers and serializers for CSV are not compliant with RFC 4180.

RFC 4180 is not an official standard. The text of the RFC itself states:

> This memo provides information for the Internet community. It does > not specify an Internet standard of any kind.

CSVs existed long before that RFC was written, and it is more a description of CSVs that are somewhat portable, not a definitive specification.

That RFC doesn't even support utf8.

It is, and accepts it is, codifing best practices rather than defining an authoritative standard.