Hello
This is expected and documented behavior:
https://www.postgresql.org/docs/current/sql-syntax-lexical.html#SQL-SYNTAX-IDENTIFIERS
> Quoting an identifier also makes it case-sensitive, whereas unquoted names are always folded to lower case. For
example,the identifiers FOO, foo, and "foo" are considered the same by PostgreSQL, but "Foo" and "FOO" are different
fromthese three and each other.
regards, Sergei