Well, I agree that philosophy can progress, but philosophy of religion isn’t the same as theology or religion itself. The philosopher’s God, known as the Absolute or the Ground of Being ends up entailing atheism, because this “god” is impersonal and mystical. Again, the religious scriptures and myths that most religious people actually revere end up being based on exoteric metaphors and mental projections, at best. So if you’re looking for philosophical progress, be careful what you wish for.
I’ve written a lot about the gap between philosophy of religion and theology/religion itself (some links below).