Misleading error "permission denied for table"

Hi hackers,
In privileges.sql there are tests for column level privileges e.g.

INSERT INTO atest5(two) VALUES (6) ON CONFLICT (two) DO UPDATE set
three = 10 RETURNING atest5.three;
ERROR: permission denied for table atest5

In the above case the current user regress_priv_user4, doesn't have
privileges to access atest5.three. But the error does not mention
atest5.three anywhere. In fact, if the same query were to be changed
to return atest5.four, it would succeed since the user has privileges
to access column atest5.four.

Shouldn't we report "permission defined for column atest5.three?

--
Best Wishes,
Ashutosh Bapat