It's all very well to point out the error of his ways but it appears no one can summon the courage to give him the old heave ho.
He is not in place. His licentiate is gone, confiscated. But he is a free citizen of Germany and can say whatever he wants and pretend to have whatever authority he wants to claim.
Part of why Hans Kung is so insanely embittered is precisely that the Vatican long ago and very publicly stripped him of the abiklity to call himself a Catholic theologian, or to teach theology in a Catholic university. He received an interdict in 1963, and was stripped of his license in 1979. Ironically, he had been responsible for getting Benedict XVI in his first teaching position.