Sec. 4. Because the management and operation of the education savings programs and all funds and accounts established under this article constitute the performance of an essential public function, the following are exempt from taxation by the state and by any political subdivision of the state:
(1) The authority's management and operations.
(2) The authority's property and assets.
(3) All property and assets held by or for the authority except individual accounts.
(4) The investment income and earnings (whether interest, gains, or dividends) on:
(A) the authority's property and assets; and
(B) all property and assets held by or for the authority;
including all funds and accounts established under this article except individual accounts.