Hardly but no more or less than a degree in Theology depedning on the individuals capacity to make good use of it.
By the nature of the Theology degree, the recipient will only benefit the members of his congregation. Where as a medical, humanities, engineering, software, arts and other degrees benefit everyone; regardless of religous affiliation.
No one is saying that you may not pursue this field of study, but the Supreme Court did say that it is up to the individual state to determine what fields of study will be supported. In this case, if you feel that you need to pursue a Theology degree, you are free to do so. You just cannot stick the taxpayers with the bill.