PL/PgSQL 'RECORD' type gotchas

CREATE OR REPLACE FUNCTION wtf1(TEXT) RETURNS RECORD
LANGUAGE plpgsql AS $$
  DECLARE
    r RECORD;
  BEGIN
    SELECT 1::INTEGER AS "a1", 2::TEXT AS "b2" INTO r;
    RETURN r;
  END;
  $$;

-- # SELECT wtf1('z');
--  wtf1
-- -------
--  (1,2)
-- (1 row)

-- # SELECT "a1" FROM wtf1('z');
-- ERROR:  a column definition list is required for functions returning "record"
-- LINE 1: SELECT "a1" FROM wtf1('z');
--                          ^

CREATE OR REPLACE FUNCTION wtf2(TEXT) RETURNS TEXT
LANGUAGE plpgsql AS $$
  DECLARE
    r RECORD;
  BEGIN
    r := wtf1($1);
    RETURN r.a1::TEXT;
  END;
  $$;

-- # SELECT wtf2('z');
--  wtf2
-- ------
--  1
-- (1 row)