Hmm it seems maybe there is an element of public funding?
either way that's not really an argument since it can just be done circularly. Some will want it to go ahead, some will not, all pay taxes, so the decision can’t be in public hands.
On balance though I think an arbitrary cancellation is a bit harsh, if it’s based on assumptions of content. I think (if this is not what happened) the venue holders should have asked him for a script or outline of the show’s content and made the decision from there. If it seemed fine from the outline and then went wildly off-piste they’d be able to say that in their defense, and would be justified in then banning him (as would other venue holders).