One might argue that this history is just that, history. Past failure does not, strictly speaking, preclude future success. Who knows? We may yet require the theistic hypothesis. That is true. But it is also true that any proposed theistic explanation comes out of a stable whose horses have previously performed badly. A prudent punter will be reluctant to put money on its future success. From a Bayesian point of view, you might argue that the past failure of the tradition of theistic explanation lowers the prior probability of any proposed theistic hypothesis. But even from the explanationist perspective which I have chosen, you can argue that past failure counts against present acceptance. It establishes what one might describe as a defeasible presumption in favour of natural explanations.