That's true. But even leaving science aside, and focusing only on non-falsifiable aspects of human ethics, there are many examples such as slavery where Christianity for example has changed over time quite radically (and not even linearly)
Surely all christians today believe that tricking somebody with dubious pretexts into debt-based slavery (as often happens with human trafficking of sex workers, where women have to formally pay up their debts and incurring the costs that they captors incur in hosting them in sub-human conditions).