The rejected legislation was contradictory: it called for both taxes on income from fortune-telling and liability for wrong predictions. Liability for wrong predictions would put fortune tellers out of business, so there’d soon be no income to tax.
(If witches’ predictions were really any good, they’d be using those supposed powers in a field with better pay and benefits than garden-variety fortune-telling.)
In any event, however dubious their trade, it’s better they’re free from state taxation.