Postgres role does not inherit permissions of superuser role via membership in that role
SUPERUSER doesn't inherit; it's an attribute of a role rather than a permission.


  The role attributes LOGIN, SUPERUSER, CREATEDB, and CREATEROLE can be thought of as special privileges, but they are never inherited as ordinary privileges on database objects are. You must actually SET ROLE to a specific role having one of these attributes in order to make use of the attribute.


See https://www.postgresql.org/docs/current/role-membership.html