There is no utility. It's perhaps written for JavaScript developers who are used to Error.. but it's not idiomatic C#. Might be indicative of a copilot too.
The use of a class-scoped `StringBuilder` that only one method uses, and `ReadQuotedColumn`/`ReadNonQuotedColumn` yielding one character at a time, rather than accepting a the builder isn't a good sign either (for efficiency). Or casting everything to a `char` (this won't support UTF8), or assuming an end quote followed by anything (:71) is valid way to end a field.
The use of a class-scoped `StringBuilder` that only one method uses, and `ReadQuotedColumn`/`ReadNonQuotedColumn` yielding one character at a time, rather than accepting a the builder isn't a good sign either (for efficiency). Or casting everything to a `char` (this won't support UTF8), or assuming an end quote followed by anything (:71) is valid way to end a field.